July 2026 - ghc-commits

[Git][ghc/ghc][wip/sjakobi/T16720] 8 commits: testsuite: Colorize the test summary, also in CI
by Simon Jakobi (＠sjakobi) 27 Jul '26

27 Jul '26

Simon Jakobi pushed to branch wip/sjakobi/T16720 at Glasgow Haskell Compiler / GHC Commits: 79bf1dbb by Simon Jakobi at 2026-07-27T14:57:17+02:00 testsuite: Colorize the test summary, also in CI The summary headings were plain, and SUMMARY was colored unconditionally, so the escapes also ended up in the file written by --summary-file. Color is now decided per output sink via term_color.colored_if; see the comments in term_color. CI logs are not a tty, but GitLab's log viewer renders ANSI colors, so add --force-colors and pass it in .gitlab/ci.sh. Assisted-by: Claude Opus 5 - - - - - c0f7ea03 by Simon Jakobi at 2026-07-27T14:57:21+02:00 testsuite: Repeat unexpected failure output in the summary Finding out why a test failed meant scrolling back through a possibly very long log to the point where the test ran. The summary now repeats the captured output of unexpected failures, before the statistics, so the interesting part is at the end of the log (#16720). Output is bounded per stream and skipped altogether beyond MAX_SUMMARY_OUTPUT_TESTS failures, pointing at the JUnit file instead; tests failing identically in several ways share one block. Test results now report a source-relative directory, which is stable regardless of where the run was started from. Assisted-by: Claude Opus 5 - - - - - 4809cc13 by Simon Jakobi at 2026-07-27T15:39:59+02:00 testsuite: Show the output diff in the failure summary Output mismatches — the most common failure kind — carried their diff but no stdout/stderr, so they showed up in the summary as a bare header with nothing under it (#16720). Report the diff too. The diff and the stream it was computed from overlap, so the mismatching stream is now dropped in favour of the diff; see Note [Redundant output in test results]. Assisted-by: Claude Opus 5 - - - - - e04b8a1d by Simon Jakobi at 2026-07-27T15:40:08+02:00 TEMP testsuite: Deliberately failing tests — DO NOT MERGE Exercises the failure-output summary (#16720) in CI: an output mismatch (in two ways, to check grouping), an stderr mismatch, a compile-time stderr mismatch, a bad exit code, and a mismatch long enough to hit the line cap. Assisted-by: Claude Opus 5 - - - - - ca92cf20 by Simon Jakobi at 2026-07-27T15:51:02+02:00 testsuite: Cap the output summary by blocks, not results The threshold for omitting repeated failure output counted (test, way) results, so a single test failing in many ways could suppress the output of the whole summary even though it collapses into one block. Group the results first, then compare the number of blocks against the threshold. Assisted-by: Claude Opus 5 - - - - - f4b52df0 by Simon Jakobi at 2026-07-27T15:55:24+02:00 testsuite: Sort the two failure summaries consistently The output summary and the test-infos listing sorted their results by different keys, so the same failures appeared in different orders. Sort both through one sorted_results helper, by (testname, directory, way): directory before way matches the grouping key of the output summary, so a test's ways stay adjacent. Assisted-by: Claude Opus 5 - - - - - 399a966a by Simon Jakobi at 2026-07-27T15:58:59+02:00 testsuite: Fall back to the absolute source path in result headers When os.path.relpath fails because there is no relative path between the test's source directory and the source root (e.g. different Windows drives), _result_directory returned '', which made the failure summary header render a bare '/' and dropped the location from the failure list entirely. Return the absolute path instead. Assisted-by: Claude Opus 5 - - - - - 3647ba9b by Simon Jakobi at 2026-07-27T16:00:52+02:00 testsuite: Fix stale comment on term_color.enable_color --force-colors also enables color, so the comment's claim that the flag comes from the tty check is no longer accurate. Assisted-by: Claude Opus 5 - - - - - 15 changed files: - .gitlab/ci.sh - testsuite/driver/runtests.py - testsuite/driver/term_color.py - testsuite/driver/testlib.py - + testsuite/tests/T16720-broken/BrokenBigStdout.hs - + testsuite/tests/T16720-broken/BrokenBigStdout.stdout - + testsuite/tests/T16720-broken/BrokenCompile.hs - + testsuite/tests/T16720-broken/BrokenCompile.stderr - + testsuite/tests/T16720-broken/BrokenExit.hs - + testsuite/tests/T16720-broken/BrokenStderr.hs - + testsuite/tests/T16720-broken/BrokenStderr.stderr - + testsuite/tests/T16720-broken/BrokenStderr.stdout - + testsuite/tests/T16720-broken/BrokenStdout.hs - + testsuite/tests/T16720-broken/BrokenStdout.stdout - + testsuite/tests/T16720-broken/all.T Changes: ===================================== .gitlab/ci.sh ===================================== @@ -652,6 +652,10 @@ function test_hadrian() { check_msys2_deps _build/stage1/bin/ghc --version check_release_build + # GitLab's log viewer renders ANSI colors, but stdout here is not a tty, + # so the driver must be told to emit them. + RUNTEST_ARGS="${RUNTEST_ARGS:-} --force-colors" + # Ensure that statically-linked builds are actually static if [[ "${BUILD_FLAVOUR}" = *static* ]]; then bad_execs="" ===================================== testsuite/driver/runtests.py ===================================== @@ -94,6 +94,8 @@ parser.add_argument("--ignore-perf-failures", choices=['increases','decreases',' help="Do not fail due to out-of-tolerance perf tests") parser.add_argument("--only-report-hadrian-deps", type=Path, help="Dry run the testsuite and report all extra hadrian dependencies needed on the given file") +parser.add_argument("--force-colors", action="store_true", + help="emit ANSI colors even when stdout is not a tty (e.g. for CI logs)") args = parser.parse_args() @@ -259,7 +261,9 @@ def supports_colors(): return True config.supports_colors = supports_colors() -term_color.enable_color = config.supports_colors +# config.supports_colors deliberately stays tty-based: it also guards +# terminal-title updates, which must not end up in a CI log. +term_color.enable_color = config.supports_colors or args.force_colors # This has to come after arg parsing as the args can change the compiler get_compiler_info() @@ -587,7 +591,7 @@ else: print(Perf.allow_changes_string([(m.change, m.stat) for m in t.metrics])) print('-' * 25) - summary(t, sys.stdout, color=config.supports_colors) + summary(t, sys.stdout, color=term_color.enable_color, junit_path=args.junit) # Write perf stats if any exist or if a metrics file is specified. stats_metrics = [stat for (_, stat, __) in t.metrics] # type: List[PerfStat] ===================================== testsuite/driver/term_color.py ===================================== @@ -1,5 +1,6 @@ from enum import Enum +# Whether to emit color escapes; set in runtests.py. enable_color = True class Color(Enum): @@ -18,3 +19,7 @@ def colored(color: Color, s: str) -> str: else: return s +# For renderers that serve several sinks: `enabled` says whether *this* sink +# takes color (the summary is written both to stdout and to a plain-text file). +def colored_if(enabled: bool, color: Color, s: str) -> str: + return colored(color, s) if enabled else s ===================================== testsuite/driver/testlib.py ===================================== @@ -27,7 +27,7 @@ from testutil import strip_quotes, lndir, link_or_copy_file, passed, \ failBecause, testing_metrics, residency_testing_metrics, \ stable_perf_counters, \ PassFail, badResult, str_warn, str_removeprefix -from term_color import Color, colored +from term_color import Color, colored_if import testutil from cpu_features import have_cpu_feature import perf_notes as Perf @@ -1497,6 +1497,19 @@ def _newTestDir(name: TestName, opts: TestOptions, tempdir, dir): opts.testdir_raw = Path(os.path.join(tempdir, testdir, name + testdir_suffix)) opts.compiler_always_flags = config.compiler_always_flags +def _result_directory(opts: TestOptions) -> str: + # The test's source directory, relative to the GHC source root, so it reads + # the same regardless of which directory `make` was invoked from. + srcdir = opts.srcdir + if srcdir is None: + return '' + try: + return os.path.relpath(srcdir, config.top.parent) + except ValueError: + # No relative path exists (e.g. different Windows drives); the + # absolute path is still more useful than nothing. + return str(srcdir) + # ----------------------------------------------------------------------------- # Actually doing tests @@ -1821,7 +1834,7 @@ async def do_test(name: TestName, if opts.expect not in ['pass', 'fail', 'missing-lib']: framework_fail(name, way, 'bad expected ' + opts.expect) - directory = str_removeprefix(str_removeprefix(str(opts.testdir), './'), '.\\') + directory = _result_directory(opts) if way in opts.fragile_ways: if_verbose(1, '*** fragile test %s resulted in %s' % (full_name, 'pass' if result.passed else 'fail')) @@ -1875,7 +1888,7 @@ def framework_fail(name: Optional[TestName], way: Optional[WayName], reason: str # so we need to take care not to blow up with the wrong way # and report the actual reason for the failure. try: - directory = str_removeprefix(str_removeprefix(str(opts.testdir), './'), '.\\') + directory = _result_directory(opts) except: directory = '' full_name = '%s(%s)' % (name, way) @@ -1888,7 +1901,7 @@ def framework_fail(name: Optional[TestName], way: Optional[WayName], reason: str def framework_warn(name: TestName, way: WayName, reason: str) -> None: opts = getTestOpts() - directory = str_removeprefix(str_removeprefix(str(opts.testdir), './'), '.\\') + directory = _result_directory(opts) full_name = name + '(' + way + ')' if_verbose(1, '*** framework warning for %s %s ' % (full_name, reason)) t.framework_warnings.append(TestResult(directory, name, reason, way)) @@ -2443,19 +2456,23 @@ async def simple_run(name: TestName, way: WayName, prog: str, extra_run_opts: st dump_stdout(name) dump_stderr(name) message = format_bad_exit_code_message(exit_code) - return failBecause(message) + return failBecause(message, + stderr=read_stderr(name), + stdout=read_stdout(name)) stderr_match = CompareOutput(True) if (opts.ignore_stderr or opts.combined_output) else await stderr_ok(name, way) if not stderr_match: + # The diff already contains the mismatching stream; see Note [Redundant + # output in test results]. return failBecause('bad stderr', - stderr=read_stderr(name), + stderr=None if stderr_match.diff else read_stderr(name), stdout=read_stdout(name), diff=stderr_match.diff) stdout_match = CompareOutput(True) if opts.ignore_stdout else await stdout_ok(name, way) if not stdout_match: return failBecause('bad stdout', stderr=read_stderr(name), - stdout=read_stdout(name), + stdout=None if stdout_match.diff else read_stdout(name), diff=stdout_match.diff) check_hp = '-hT' in my_rts_flags and opts.check_hp @@ -2565,8 +2582,9 @@ async def interpreter_run(name: TestName, if not stderr_match: if _expect_pass(way): dump_stderr_for('comp', name) + # See Note [Redundant output in test results]. return failBecause('bad stderr', - stderr=read_stderr(name), + stderr=None if stderr_match.diff else read_stderr(name), stdout=read_stdout(name), diff=stderr_match.diff) stdout_match = CompareOutput(True) if opts.ignore_stdout else await stdout_ok(name, way) @@ -2575,7 +2593,7 @@ async def interpreter_run(name: TestName, dump_stderr_for('comp', name) return failBecause('bad stdout', stderr=read_stderr(name), - stdout=read_stdout(name), + stdout=None if stdout_match.diff else read_stdout(name), diff=stdout_match.diff) return passed() @@ -3569,12 +3587,50 @@ def findTFiles(roots: List[str]) -> Iterator[str]: # ----------------------------------------------------------------------------- # Output a test summary to the specified file object -def summary(t: TestRun, file: TextIO, color=False) -> None: +def summary(t: TestRun, file: TextIO, color=False, junit_path: Optional[Path]=None) -> None: file.write('\n') + + if t.unexpected_failures: + # Count output blocks rather than results: a test failing in many ways + # collapses to a single block. + groups = groupTestOutput(t.unexpected_failures) + if len(groups) <= MAX_SUMMARY_OUTPUT_TESTS: + printTestOutputSummary(file, groups, color, junit_path) + else: + where = '; see {}'.format(junit_path) if junit_path else '' + header = ('Unexpected failures (more than {}, output omitted{}):' + .format(MAX_SUMMARY_OUTPUT_TESTS, where)) + file.write(colored_if(color, Color.RED, header) + '\n') + printTestInfosSummary(file, t.unexpected_failures) + + if t.unexpected_passes: + header = 'Unexpected passes:' + file.write(colored_if(color, Color.RED, header) + '\n') + printTestInfosSummary(file, t.unexpected_passes) + + if t.unexpected_stat_failures: + header = 'Unexpected stat failures:' + file.write(colored_if(color, Color.RED, header) + '\n') + printTestInfosSummary(file, t.unexpected_stat_failures) + + if t.framework_failures: + header = 'Framework failures:' + file.write(colored_if(color, Color.RED, header) + '\n') + printTestInfosSummary(file, t.framework_failures) + + if t.framework_warnings: + header = 'Framework warnings:' + file.write(colored_if(color, Color.YELLOW, header) + '\n') + printTestInfosSummary(file, t.framework_warnings) + + if stopping(): + warning = 'WARNING: Testsuite run was terminated early' + file.write(colored_if(color, Color.YELLOW, warning) + '\n') + printUnexpectedTests(file, [t.unexpected_passes, t.unexpected_failures, - t.unexpected_stat_failures, t.framework_failures]) + t.unexpected_stat_failures, t.framework_failures], color) if len(t.unexpected_failures) > 0 or \ len(t.unexpected_stat_failures) > 0 or \ @@ -3585,7 +3641,8 @@ def summary(t: TestRun, file: TextIO, color=False) -> None: summary_color = Color.GREEN assert t.start_time is not None - file.write(colored(summary_color, 'SUMMARY') + ' for test run started at ' + summary_header = colored_if(color, summary_color, 'SUMMARY') + file.write(summary_header + ' for test run started at ' + t.start_time.strftime("%c %Z") + '\n' + str(datetime.datetime.now() - t.start_time).rjust(8) + ' spent to go through\n' @@ -3617,46 +3674,102 @@ def summary(t: TestRun, file: TextIO, color=False) -> None: + ' fragile tests\n' + '\n') - if t.unexpected_passes: - file.write('Unexpected passes:\n') - printTestInfosSummary(file, t.unexpected_passes) - - if t.unexpected_failures: - file.write('Unexpected failures:\n') - printTestInfosSummary(file, t.unexpected_failures) - - if t.unexpected_stat_failures: - file.write('Unexpected stat failures:\n') - printTestInfosSummary(file, t.unexpected_stat_failures) - - if t.framework_failures: - file.write('Framework failures:\n') - printTestInfosSummary(file, t.framework_failures) - - if t.framework_warnings: - file.write('Framework warnings:\n') - printTestInfosSummary(file, t.framework_warnings) - - if stopping(): - file.write('WARNING: Testsuite run was terminated early\n') - -def printUnexpectedTests(file: TextIO, testInfoss): +def printUnexpectedTests(file: TextIO, testInfoss, color=False): unexpected = set(result.testname for testInfos in testInfoss for result in testInfos if not result.testname.endswith('.T')) if unexpected: - file.write('Unexpected results from:\n') + header = 'Unexpected results from:' + file.write(colored_if(color, Color.RED, header) + '\n') file.write('TEST="' + ' '.join(sorted(unexpected)) + '"\n') file.write('\n') +# Per-stream cap on a failing test's output repeated in the final summary. +MAX_SUMMARY_OUTPUT_LINES = 100 + +# Above this many output blocks, skip repeating output entirely: the dump +# would drown out the summary. +MAX_SUMMARY_OUTPUT_TESTS = 20 + +""" +Note [Redundant output in test results] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +A failing test result carries up to three pieces of output: `diff`, `stdout` +and `stderr`. For an output mismatch these overlap: the diff's `+` lines are +the very stream that mismatched, normalised. Reporting both would print the +same text twice, so the mismatching stream is dropped at the call sites in +favour of the diff, which additionally shows what was expected. The *other* +stream is kept: on a stdout mismatch, stderr is independent context. + +The drop is conditional on there being a diff at all: compare_outputs only +runs `diff` when config.verbose >= 1, so under -v0 the stream is the only +output there is. +""" + +def strip_diff_header(diff: Optional[str]) -> Optional[str]: + # Drop diff(1)'s ---/+++ lines: they name normalised files in the test + # directory and carry timestamps, which would also keep otherwise + # identical failures from being grouped. + if diff is None: + return None + lines = diff.split('\n') + if len(lines) >= 2 and lines[0].startswith('--- ') and lines[1].startswith('+++ '): + return '\n'.join(lines[2:]) + return diff + +def sorted_results(testInfos: List[TestResult]) -> List[TestResult]: + return sorted(testInfos, key=lambda r: (r.testname.lower(), r.directory, r.way)) + +# Tests that fail identically in several ways (e.g. normal and g1) share one +# output block, with the ways collected in the header. +def groupTestOutput(testInfos: List[TestResult] + ) -> List[Tuple[TestResult, str, List[WayName]]]: + groups = collections.OrderedDict() # type: ignore + for result in sorted_results(testInfos): + diff = strip_diff_header(result.diff) + key = (result.testname, result.directory, result.reason, + diff, result.stdout, result.stderr) + groups.setdefault(key, (result, diff, []))[2].append(result.way) + return list(groups.values()) + +def printTestOutputSummary(file: TextIO, + groups: List[Tuple[TestResult, str, List[WayName]]], + color: bool=False, + junit_path: Optional[Path]=None) -> None: + # Repeat failing tests' captured output in the summary, so one needn't + # hunt for it earlier in a possibly very long log; see #16720. + header = '=====> Unexpected failures output summary' + file.write(colored_if(color, Color.RED, header) + '\n\n') + + where = ', see {}'.format(junit_path) if junit_path else '' + for result, diff, ways in groups: + header = '=====> {}({}) ({}) [{}]'.format( + result.testname, ', '.join(ways), result.directory + os.sep, result.reason) + file.write(colored_if(color, Color.RED, header) + '\n') + # See Note [Redundant output in test results] for why these don't overlap. + for label, contents in [('Output diff (expected vs actual):', diff), + ('Captured stdout:', result.stdout), + ('Captured stderr:', result.stderr)]: + if contents and contents.strip(): + lines = contents.rstrip('\n').split('\n') + if len(lines) > MAX_SUMMARY_OUTPUT_LINES: + omitted = len(lines) - MAX_SUMMARY_OUTPUT_LINES + lines = lines[:MAX_SUMMARY_OUTPUT_LINES] \ + + ['... ({} more lines omitted{})'.format(omitted, where)] + s = colored_if(color, Color.CYAN, label) + '\n' \ + + ''.join(l + '\n' for l in lines) + # Test output can contain characters that file's encoding + # cannot represent; replace rather than crash (cf safe_print). + enc = getattr(file, 'encoding', None) or 'utf-8' + file.write(s.encode(enc, errors='replace').decode(enc)) + footer = '<===== end of unexpected failures output summary' + file.write(colored_if(color, Color.RED, footer) + '\n\n') + def printTestInfosSummary(file: TextIO, testInfos): - maxDirLen = max(len(tr.directory) for tr in testInfos) - for result in sorted(testInfos, key=lambda r: (r.testname.lower(), r.way, r.directory)): - directory = result.directory.ljust(maxDirLen) - file.write(' {directory} {r.testname} [{r.reason}] ({r.way})\n'.format( - r = result, - directory = directory)) + for result in sorted_results(testInfos): + path = os.path.join(result.directory, result.testname) + file.write(' {path} [{r.reason}] ({r.way})\n'.format(r=result, path=path)) file.write('\n') def modify_lines(s: str, f: Callable[[str], str]) -> str: ===================================== testsuite/tests/T16720-broken/BrokenBigStdout.hs ===================================== @@ -0,0 +1,2 @@ +main :: IO () +main = mapM_ (\i -> putStrLn ("actual line " ++ show i)) [1 :: Int ..150] ===================================== testsuite/tests/T16720-broken/BrokenBigStdout.stdout ===================================== @@ -0,0 +1,150 @@ +expected line 1 +expected line 2 +expected line 3 +expected line 4 +expected line 5 +expected line 6 +expected line 7 +expected line 8 +expected line 9 +expected line 10 +expected line 11 +expected line 12 +expected line 13 +expected line 14 +expected line 15 +expected line 16 +expected line 17 +expected line 18 +expected line 19 +expected line 20 +expected line 21 +expected line 22 +expected line 23 +expected line 24 +expected line 25 +expected line 26 +expected line 27 +expected line 28 +expected line 29 +expected line 30 +expected line 31 +expected line 32 +expected line 33 +expected line 34 +expected line 35 +expected line 36 +expected line 37 +expected line 38 +expected line 39 +expected line 40 +expected line 41 +expected line 42 +expected line 43 +expected line 44 +expected line 45 +expected line 46 +expected line 47 +expected line 48 +expected line 49 +expected line 50 +expected line 51 +expected line 52 +expected line 53 +expected line 54 +expected line 55 +expected line 56 +expected line 57 +expected line 58 +expected line 59 +expected line 60 +expected line 61 +expected line 62 +expected line 63 +expected line 64 +expected line 65 +expected line 66 +expected line 67 +expected line 68 +expected line 69 +expected line 70 +expected line 71 +expected line 72 +expected line 73 +expected line 74 +expected line 75 +expected line 76 +expected line 77 +expected line 78 +expected line 79 +expected line 80 +expected line 81 +expected line 82 +expected line 83 +expected line 84 +expected line 85 +expected line 86 +expected line 87 +expected line 88 +expected line 89 +expected line 90 +expected line 91 +expected line 92 +expected line 93 +expected line 94 +expected line 95 +expected line 96 +expected line 97 +expected line 98 +expected line 99 +expected line 100 +expected line 101 +expected line 102 +expected line 103 +expected line 104 +expected line 105 +expected line 106 +expected line 107 +expected line 108 +expected line 109 +expected line 110 +expected line 111 +expected line 112 +expected line 113 +expected line 114 +expected line 115 +expected line 116 +expected line 117 +expected line 118 +expected line 119 +expected line 120 +expected line 121 +expected line 122 +expected line 123 +expected line 124 +expected line 125 +expected line 126 +expected line 127 +expected line 128 +expected line 129 +expected line 130 +expected line 131 +expected line 132 +expected line 133 +expected line 134 +expected line 135 +expected line 136 +expected line 137 +expected line 138 +expected line 139 +expected line 140 +expected line 141 +expected line 142 +expected line 143 +expected line 144 +expected line 145 +expected line 146 +expected line 147 +expected line 148 +expected line 149 +expected line 150 ===================================== testsuite/tests/T16720-broken/BrokenCompile.hs ===================================== @@ -0,0 +1,4 @@ +module BrokenCompile where + +foo :: Int +foo = "not an Int" ===================================== testsuite/tests/T16720-broken/BrokenCompile.stderr ===================================== @@ -0,0 +1,6 @@ + +BrokenCompile.hs:4:7: error: [GHC-83865] + • Couldn't match expected type: Bool + with actual type: Int + • In the expression: "not an Int" + In an equation for 'foo': foo = "not an Int" ===================================== testsuite/tests/T16720-broken/BrokenExit.hs ===================================== @@ -0,0 +1,8 @@ +import System.Exit +import System.IO + +main :: IO () +main = do + putStrLn "some stdout before dying" + hPutStrLn stderr "some stderr before dying" + exitWith (ExitFailure 3) ===================================== testsuite/tests/T16720-broken/BrokenStderr.hs ===================================== @@ -0,0 +1,6 @@ +import System.IO + +main :: IO () +main = do + putStrLn "this stdout is fine and independent of the stderr mismatch" + hPutStrLn stderr "actual complaint" ===================================== testsuite/tests/T16720-broken/BrokenStderr.stderr ===================================== @@ -0,0 +1 @@ +expected complaint ===================================== testsuite/tests/T16720-broken/BrokenStderr.stdout ===================================== @@ -0,0 +1 @@ +this stdout is fine and independent of the stderr mismatch ===================================== testsuite/tests/T16720-broken/BrokenStdout.hs ===================================== @@ -0,0 +1,5 @@ +main :: IO () +main = do + putStrLn "line one" + putStrLn "actual line two" + putStrLn "line three" ===================================== testsuite/tests/T16720-broken/BrokenStdout.stdout ===================================== @@ -0,0 +1,3 @@ +line one +expected line two +line three ===================================== testsuite/tests/T16720-broken/all.T ===================================== @@ -0,0 +1,8 @@ +# Deliberately failing tests, to exercise the failure-output summary (#16720). +# NOT FOR MERGE — drop this directory before the MR is merged. + +test('BrokenStdout', extra_ways(['optasm']), compile_and_run, ['']) +test('BrokenStderr', normal, compile_and_run, ['']) +test('BrokenExit', normal, compile_and_run, ['']) +test('BrokenCompile', normal, compile_fail, ['']) +test('BrokenBigStdout', normal, compile_and_run, ['']) View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/a38f657ea5d7d31031730d546d32b8… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/a38f657ea5d7d31031730d546d32b8… You're receiving this email because of your account on gitlab.haskell.org. Manage all notifications: https://gitlab.haskell.org/-/profile/notifications | Help: https://gitlab.haskell.org/help

1 0

[Git][ghc/ghc][wip/9.14.2-backports] 2 commits: UniqueDFM: alter should preserve insertion order
by Zubin (＠wz1000) 27 Jul '26

27 Jul '26

Zubin pushed to branch wip/9.14.2-backports at Glasgow Haskell Compiler / GHC Commits: 47e46cc8 by Zubin Duggal at 2026-07-27T18:57:26+05:30 UniqueDFM: alter should preserve insertion order Before it always inserting new elements at the end. This is problematic because instances get inserted into the map with `alterF`, which can change ordering of how instances are printed with `:info` depending on the order in which we consult interfaces I expect `alter id k = id` and `alter (fmap f) k = adjust f k`. Moving keys to the end breaks that (`adjust` already preserves position). Fixes #27532 (cherry picked from commit f6f2343fbbfdfd8aaed9babf5983e3e24c08ca85) - - - - - dd581d84 by Zubin Duggal at 2026-07-27T18:57:26+05:30 Prepare 9.14.2 Bump filpath submodule to 1.5.5.0 Bump Win32 submodule to 2.14.2.2 Metric Increase: T4029 T13379 Metric Decrease: T5030 - - - - - 68 changed files: - − changelog.d/26616 - − changelog.d/T26978 - − changelog.d/T26979 - − changelog.d/T27046 - − changelog.d/T27047 - − changelog.d/T27123.md - − changelog.d/T27124.md - − changelog.d/T27131 - − changelog.d/T27182.md - − changelog.d/T27202 - − changelog.d/T27225 - − changelog.d/T27386 - − changelog.d/bump-process - − changelog.d/deterministic-usage-order - − changelog.d/fix-absent-dict-projection - − changelog.d/fix-blackhole-handling - − changelog.d/fix-cmm-atomic-load-store - − changelog.d/fix-compacting-gc-ap-27434 - − changelog.d/fix-exponential-case-desugar-27383 - − changelog.d/fix-finalizers-27072 - − changelog.d/fix-layout-stack-fcall - − changelog.d/fix-peekitbl-no-tntc - − changelog.d/fix-use-std-ap-thunk - − changelog.d/ghc-pkg-faster-closure - − changelog.d/hadrian-stale-package-confs-26661 - − changelog.d/jobserver-leak-fix - − changelog.d/more-efficient-home-unit-imports-finding - − changelog.d/reexported-module-errors - − changelog.d/semaphore-v2 - − changelog.d/tag-inference-27005 - − changelog.d/unused-type - − changelog.d/wasm-fix-serviceworker - − changelog.d/windows-rethrow-overlapped-exception - compiler/GHC/Types/Unique/DFM.hs - configure.ac - docs/users_guide/9.14.2-notes.rst - hadrian/bootstrap/generate_bootstrap_plans - + hadrian/bootstrap/plan-9_10_3.json - + hadrian/bootstrap/plan-9_12_4.json - + hadrian/bootstrap/plan-bootstrap-9_10_3.json - + hadrian/bootstrap/plan-bootstrap-9_12_4.json - libraries/Win32 - libraries/base/base.cabal.in - libraries/base/changelog.md - libraries/filepath - testsuite/tests/ghci/T16793/T16793.stdout - testsuite/tests/ghci/T18060/T18060.stdout - + testsuite/tests/ghci/T27532/Makefile - + testsuite/tests/ghci/T27532/T27532.script - + testsuite/tests/ghci/T27532/T27532.stdout - + testsuite/tests/ghci/T27532/all.T - testsuite/tests/ghci/scripts/ListTuplePunsPpr.stdout - testsuite/tests/ghci/scripts/T4175.stdout - testsuite/tests/ghci/scripts/T8469.stdout - testsuite/tests/ghci/scripts/T8535.stdout - testsuite/tests/ghci/scripts/T9881.stdout - testsuite/tests/ghci/scripts/ghci020.stdout - testsuite/tests/ghci/scripts/ghci064.stdout - testsuite/tests/ghci/should_run/T10145.stdout - testsuite/tests/ghci/should_run/T18594.stdout - testsuite/tests/partial-sigs/should_compile/ExtraConstraints3.stderr - testsuite/tests/roles/should_compile/Roles14.stderr - testsuite/tests/roles/should_compile/Roles3.stderr - testsuite/tests/roles/should_compile/Roles4.stderr - testsuite/tests/roles/should_compile/T8958.stderr - testsuite/tests/typecheck/should_compile/T18406b.stderr - testsuite/tests/typecheck/should_compile/T18529.stderr - testsuite/tests/typecheck/should_fail/T5300.stderr The diff was not included because it is too large. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/a2bb906948aeb3ebf1a1bfb4bedbab… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/a2bb906948aeb3ebf1a1bfb4bedbab… You're receiving this email because of your account on gitlab.haskell.org. Manage all notifications: https://gitlab.haskell.org/-/profile/notifications | Help: https://gitlab.haskell.org/help

1 0

[Git][ghc/ghc][wip/9.14.2-backports] 5 commits: JS: fix array index for registers
by Zubin (＠wz1000) 27 Jul '26

27 Jul '26

Zubin pushed to branch wip/9.14.2-backports at Glasgow Haskell Compiler / GHC Commits: 7f030f76 by Sylvain Henry at 2026-07-27T18:52:57+05:30 JS: fix array index for registers We used to store R32 in h$regs[-1]. While it's correct in JavaScript, fix this to store R32 in h$regs[0] instead. (cherry picked from commit c9fa3449d78f4fe690acf26a57b1e338a2d580da) - - - - - 2ee8bc10 by Sylvain Henry at 2026-07-27T18:52:57+05:30 JS: support more than 128 registers (#26558) The JS backend only supported 128 registers (JS variables/array slots used to pass function arguments). It failed in T26537 when 129 registers were required. This commit adds support for more than 128 registers: it is now limited to maxBound :: Int (compiler's Int). If we ever go above this threshold the compiler now panics with a more descriptive message. A few built-in JS functions were assuming 128 registers and have been rewritten to use loops. Note that loops are only used for "high" registers that are stored in an array: the 31 "low" registers are still handled with JS global variables and with explicit switch-cases to maintain good performance in the most common cases (i.e. few registers used). Adjusting the number of low registers is now easy: just one constant to adjust (GHC.StgToJS.Regs.lowRegsCount). No new test added: T26537 is used as a regression test instead. (cherry picked from commit 9e46990976193d71686b070cd4c5d9c7aad43cf2) - - - - - f817f41a by Andreas Klebinger at 2026-07-27T18:52:57+05:30 testsuite: Explicitly use utf-8 encoding in rts-includes linter. Not doing so caused failures on windows, as python failed to pick a reasonable encoding even with locale set. Fixes #26850 (cherry picked from commit 01ecb61234b03b94d08ab649395e2da074a4f9d3) - - - - - 433fe334 by Zubin Duggal at 2026-07-27T18:52:57+05:30 UniqueDFM: alter should preserve insertion order Before it always inserting new elements at the end. This is problematic because instances get inserted into the map with `alterF`, which can change ordering of how instances are printed with `:info` depending on the order in which we consult interfaces I expect `alter id k = id` and `alter (fmap f) k = adjust f k`. Moving keys to the end breaks that (`adjust` already preserves position). Fixes #27532 (cherry picked from commit f6f2343fbbfdfd8aaed9babf5983e3e24c08ca85) - - - - - a2bb9069 by Zubin Duggal at 2026-07-27T18:52:57+05:30 Prepare 9.14.2 Bump filpath submodule to 1.5.5.0 Bump Win32 submodule to 2.14.2.2 Metric Increase: T4029 T13379 Metric Decrease: T5030 - - - - - 77 changed files: - − changelog.d/26616 - − changelog.d/T26978 - − changelog.d/T26979 - − changelog.d/T27046 - − changelog.d/T27047 - − changelog.d/T27123.md - − changelog.d/T27124.md - − changelog.d/T27131 - − changelog.d/T27182.md - − changelog.d/T27202 - − changelog.d/T27225 - − changelog.d/T27386 - − changelog.d/bump-process - − changelog.d/deterministic-usage-order - − changelog.d/fix-absent-dict-projection - − changelog.d/fix-blackhole-handling - − changelog.d/fix-cmm-atomic-load-store - − changelog.d/fix-compacting-gc-ap-27434 - − changelog.d/fix-exponential-case-desugar-27383 - − changelog.d/fix-finalizers-27072 - − changelog.d/fix-layout-stack-fcall - − changelog.d/fix-peekitbl-no-tntc - − changelog.d/fix-use-std-ap-thunk - − changelog.d/ghc-pkg-faster-closure - − changelog.d/hadrian-stale-package-confs-26661 - − changelog.d/jobserver-leak-fix - − changelog.d/more-efficient-home-unit-imports-finding - − changelog.d/reexported-module-errors - − changelog.d/semaphore-v2 - − changelog.d/tag-inference-27005 - − changelog.d/unused-type - − changelog.d/wasm-fix-serviceworker - − changelog.d/windows-rethrow-overlapped-exception - compiler/GHC/StgToJS/Apply.hs - compiler/GHC/StgToJS/Expr.hs - compiler/GHC/StgToJS/Regs.hs - compiler/GHC/StgToJS/Rts/Rts.hs - compiler/GHC/StgToJS/Rts/Types.hs - compiler/GHC/Types/Unique/DFM.hs - configure.ac - docs/users_guide/9.14.2-notes.rst - hadrian/bootstrap/generate_bootstrap_plans - + hadrian/bootstrap/plan-9_10_3.json - + hadrian/bootstrap/plan-9_12_4.json - + hadrian/bootstrap/plan-bootstrap-9_10_3.json - + hadrian/bootstrap/plan-bootstrap-9_12_4.json - libraries/Win32 - libraries/base/base.cabal.in - libraries/base/changelog.md - libraries/filepath - testsuite/tests/codeGen/should_run/all.T - testsuite/tests/ghci/T16793/T16793.stdout - testsuite/tests/ghci/T18060/T18060.stdout - + testsuite/tests/ghci/T27532/Makefile - + testsuite/tests/ghci/T27532/T27532.script - + testsuite/tests/ghci/T27532/T27532.stdout - + testsuite/tests/ghci/T27532/T27532j4.stdout - + testsuite/tests/ghci/T27532/all.T - + testsuite/tests/ghci/T27532/genT27532Modules - testsuite/tests/ghci/scripts/ListTuplePunsPpr.stdout - testsuite/tests/ghci/scripts/T4175.stdout - testsuite/tests/ghci/scripts/T8469.stdout - testsuite/tests/ghci/scripts/T8535.stdout - testsuite/tests/ghci/scripts/T9881.stdout - testsuite/tests/ghci/scripts/ghci020.stdout - testsuite/tests/ghci/scripts/ghci064.stdout - testsuite/tests/ghci/should_run/T10145.stdout - testsuite/tests/ghci/should_run/T18594.stdout - testsuite/tests/linters/regex-linters/check-rts-includes.py - testsuite/tests/partial-sigs/should_compile/ExtraConstraints3.stderr - testsuite/tests/roles/should_compile/Roles14.stderr - testsuite/tests/roles/should_compile/Roles3.stderr - testsuite/tests/roles/should_compile/Roles4.stderr - testsuite/tests/roles/should_compile/T8958.stderr - testsuite/tests/typecheck/should_compile/T18406b.stderr - testsuite/tests/typecheck/should_compile/T18529.stderr - testsuite/tests/typecheck/should_fail/T5300.stderr The diff was not included because it is too large. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/39eaaa6599c174fdb21edd1f17ac6a… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/39eaaa6599c174fdb21edd1f17ac6a… You're receiving this email because of your account on gitlab.haskell.org. Manage all notifications: https://gitlab.haskell.org/-/profile/notifications | Help: https://gitlab.haskell.org/help

1 0

[Git][ghc/ghc] Pushed new branch wip/sjakobi/ci-ignore-perf-failures
by Simon Jakobi (＠sjakobi) 27 Jul '26

27 Jul '26

Simon Jakobi pushed new branch wip/sjakobi/ci-ignore-perf-failures at Glasgow Haskell Compiler / GHC -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/tree/wip/sjakobi/ci-ignore-perf-failur… You're receiving this email because of your account on gitlab.haskell.org. Manage all notifications: https://gitlab.haskell.org/-/profile/notifications | Help: https://gitlab.haskell.org/help

1 0

[Git][ghc/ghc][wip/sjakobi/T16720] 94 commits: Add 'backendInfoTableMapValidity' backend predicate
by Simon Jakobi (＠sjakobi) 27 Jul '26

27 Jul '26

Simon Jakobi pushed to branch wip/sjakobi/T16720 at Glasgow Haskell Compiler / GHC Commits: 66d1a5d5 by fendor at 2026-07-07T16:57:56-04:00 Add 'backendInfoTableMapValidity' backend predicate Check whether the backend supports the `-finfo-table-map` flag and ignore it otherwise. Improve by-design documentation of `backendCodeOutput`. `Backend` is **abstract by design**. Make this clearer in `backendCodeOutput` which is incorrectly being used as a proxy for `Backend`. Instead, define the desired property predicates in GHC.Driver.Backend In the process, make `backendCodeOutput` total. - - - - - 74f1071d by fendor at 2026-07-07T16:57:56-04:00 Add failing test for `-finfo-table-map` and bytecode backend If you compile a module using the bytecode backend, with -finfo-table-map, then the info table map doesn't get populated for the module. This is because the -finfo-table-map code path is implemented mostly in the StgToCmm phase which isn't run when creating bytecode. Ticket #27039 - - - - - 28d63bca by mangoiv at 2026-07-07T16:59:16-04:00 ci: don't fail nightly if there have been no changes that night Fixes #27127 - - - - - 4ebfc478 by Rodrigo Mesquita at 2026-07-08T04:47:53-04:00 ttg: Using ShortText over FastString in the AST To make the AST independent of GHC, this commit replaces usages of `FastString` with `HText` in the AST, killing the last edge from Language.Haskell.* to GHC.* modules. Even though we /do/ want to use FastStrings in general -- critically in Names or Ids -- there is no particular reason for the FastStrings that occur in the AST proper to be FastStrings. Strings in the AST are typically unique and don't benefit particularly from being interned FastStrings with Uniques for fast comparison. `HText` is a type synonym for `ShortText` which uses GHC's Modified UTF-8 encoding exclusively. Modified UTF-8 must be used to represent the Haskell AST because the Haskell Report allows surrogate code points. `Data.Text.Text` functions use Standard UTF-8 which replace surrogates with a placeholder value, thus `Data.Text.Text` is unsuitable for AST strings. See the `Language.Haskell.Syntax.Text` module header for more details. Final progress towards #21592 Closes #21628 - - - - - d910b353 by Simon Peyton Jones at 2026-07-08T04:48:36-04:00 Update equality-type documenation in GHC.Builtin.Types.Prim Fix #27466 - - - - - b2530542 by Simon Peyton Jones at 2026-07-08T04:48:36-04:00 Honour -dsuppress-coercions in GHC.Core.TyCo.pprCo Fixes #27467 - - - - - 9a73179a by Facundo Domínguez at 2026-07-08T04:49:26-04:00 Add item to MR checklist asking to squash fixup commits after approval The checklist has an item that reads All commits are either individually buildable or squashed. This item could be checked immediately after sending the merge request though. If reviewers ask for amends later on, and the author amends the merge request, there was no item that would remind the contributors to squash the fixup commits before landing. This commit adds a new item After all approvals and before landing: all fixup commits are squashed with their originating commits. which should be harder to mark as done before approvals have been given. - - - - - ed09895d by Andreas Klebinger at 2026-07-08T16:53:27-04:00 Fix a profiling race condition resulting in segfaults. StgToCmm: Don't assume tagged FUN closures in closureCodeBody. When entering a closure the self/node pointer might not be tagged in some situations when a thunk is evaluated by multiple threads. So we most AND away the tag bits rather than subtracting an expected tag. Apply.cmm: Fix a race condition occuring when a thunk is mutated during GC. In stg_ap_0_fast when might need to run GC before entering a thunk. If this happens another thread or the GC itself might mutate the closure making entering it no longer valid. We now check for this. Add test and changelog for #27123 fixes. - - - - - 67c03eb2 by Cheng Shao at 2026-07-08T16:54:09-04:00 ghc-heap: fix invalid srtlen returned by peekItbl when no-TNTC This patch fixes the no-TNTC code path of `peekItbl` so that it looks at the right memory address when reading the `srt` field from the `StgInfoTable_` struct. Also adds a `T27465` regression test that reproduces the bug on no-TNTC builds before the fix. Fixes #27465. Co-authored-by: Codex <codex(a)openai.com> - - - - - 2ecabb4f by Zubin Duggal at 2026-07-09T09:23:25-04:00 hadrian: binary-dist-dir should not be the default target Revert behaviour to pre 23c9b6c392f52ec9d7a8618b204ff6b885f5fba2 In 23c9b6c392f52ec9d7a8618b204ff6b885f5fba2, we applied the following behaviour change: ``` hadrian: Build stage 2 cross compilers ... * hadrian: Make binary-dist-dir the default build target. This allows us to have the logic in one place about which libraries/stages to build with cross compilers. Fixes #24192 ``` This is a major regression to development experience, a plain hadrian/build --freeze1 now takes ages because we rebuild all docs (which need to go in the binary dist dir). `binary-dist-dir` is the wrong default target for regular GHC development work Fixes #27445 - - - - - e16388e3 by Zubin Duggal at 2026-07-09T09:23:25-04:00 .gitignore: Add the hadrian system.config introduced by commit 23c9b6c392f52ec9d7a8618b204ff6b885f5fba2 Since commit 23c9b6c392f52ec9d7a8618b204ff6b885f5fba2 Author: Matthew Pickering <matthewtpickering(a)gmail.com> Date: Thu Dec 21 16:17:41 2023 +0000 hadrian: Build stage 2 cross compilers ./configure produces /hadrian/cfg/system.config.{host,target} Add these to .gitignore - - - - - 7e8abf41 by Alan Zimmerman at 2026-07-09T09:24:12-04:00 EPA: Replace AnnListItem with simply [TrailingAnn] Remove the unnecessary wrapper around a single field. - - - - - 29032f17 by Zubin Duggal at 2026-07-09T09:24:58-04:00 testsuite: Keep real reason for fragile test failures - - - - - c34e03a7 by Zubin Duggal at 2026-07-09T09:24:58-04:00 testsuite: Fall back to the failure reason for empty JUnit bodies - - - - - 409d40f0 by Zubin Duggal at 2026-07-09T09:24:58-04:00 testsuite: Show output diffs in JUnit output Also refactor compare_outputs to return essentially a `Maybe Diff` (`CompareOutput`) instead of a bool, but more pythonic. This allows us to pass the diff through nice. - - - - - 06fee1ab by Zubin Duggal at 2026-07-09T09:24:58-04:00 perf notes: include stat deviation and acceptance window in notes so they show up in gitlab - - - - - 57c0f32c by mangoiv at 2026-07-10T11:08:38-04:00 driver: enable -finter-module-far-jumps by default this fixes a compatibility bug with certain binutils/gcc versions where we were seeing jump offset overflow errors. This commit can probably reverted if we stop supporting the problematic binutils/gcc verions (2.44 and 14.2, respectively) Reolves #26994 - - - - - 4396a6f2 by Andrea Vezzosi at 2026-07-10T11:09:25-04:00 [Fix #27287] preserve ModBreaks in ModIface - - - - - ed261a7e by Cheng Shao at 2026-07-14T17:59:38-04:00 hadrian: fix HLS support This patch fixes hadrian's HLS support so one can rely on HLS when working on the hadrian codebase. Fixes #27480. Not building/linking shared libraries for hadrian is a severely premature optimization; this top-level setting in `cabal.project` only affects home packages while the dependencies in the cabal store are built with vanilla/dynamic anyway, and even adding dynamic builds to home packages would not be costly due to cabal's usage of `-dynamic-too`. - - - - - eee8ec5b by Cheng Shao at 2026-07-14T18:00:20-04:00 compiler: fix miscompiled %load_relaxed, add missing %store_relaxed This patch fixes the %load_relaxed cmm primop compilation logic to correctly use relaxed memory ordering, and adds the missing %store_relaxed primop. Parsing logic of %load/%store with explicit ordering is covered in the AtomicFetch test case. Fixes #27483. Co-authored-by: Codex <codex(a)openai.com> - - - - - 1718230f by Alan Zimmerman at 2026-07-14T18:01:06-04:00 EPA: Keep binds and sigs together in HsValBindsLR We combine them into a single list for GhcPs, wrapped in the ValBind data type, which is the bind equivalent of ValD, having constructors for binds and sigs. This simplifies exact print processing, especially when using it to update the contents of local binds, as we no longer need AnnSortKey BindTag - - - - - 6bd1ad2a by Andreas Klebinger at 2026-07-14T18:01:49-04:00 Bump nofib submodule to account for MonoLocalBinds. New versions of GHC enable MonoLocalBinds by default. This breaks some of the benchmarks. I've fixed this and this bump pulls in that fix. - - - - - 7eb0f1c9 by Cheng Shao at 2026-07-14T18:02:31-04:00 testsuite: fix bytecodeIPE test under +ipe flavours This patch fixes the bytecodeIPE test under +ipe flavours. It used to fail under +ipe because the RTS is built with IPE info, then stg_AP_info in RTS carries IPE info, so whereFrom wouldn't return Nothing. Now the test checks IPE info of a datacon in the ghci-loaded module which is not affected by whether the RTS is built with IPE info or not. Fixes #27498. Co-authored-by: Codex <codex(a)openai.com> - - - - - ef038aae by cydparser at 2026-07-15T04:35:41-04:00 Reduce bytes allocated for `capabilities` in RTS (fixes #27487) In rts/Capability.c, `capabilities` is an array of pointers, but it was allocated as if it were an array of Capability's. - - - - - d377e83e by Cheng Shao at 2026-07-15T04:36:27-04:00 rts: fix missing UNTAG in stg_readTVarIOzh This patch fixes missing UNTAG on the current value closure read from StgTVar. UNTAG is a no-op when it's stg_TREC_HEADER_info which is word aligned; it may be a tagged closure, and reading info table from the tagged address is an unaligned load which may cause issues on platforms with strict alignment requirements. Co-authored-by: Codex <codex(a)openai.com> - - - - - 8ed03842 by Cheng Shao at 2026-07-15T04:36:27-04:00 rts: fix missing UNTAG in stg_control0zh_ll This patch fixes missing UNTAG on the cont closure returned by captureContinuationAndAbort. In case it's not NULL, captureContinuationAndAbort returns a tagged StgContinuation closure, in which case it must be untagged before accessing the apply_mask_frame field. In the past it worked out of luck: when apply_mask_frame was NULL then mask_frame_offset is also 0 so the control flow didn't diverge to a wrong path. Still, this is horribly wrong and will crash once StgContinuation struct is refactored and fields are shuffled around. Co-authored-by: Codex <codex(a)openai.com> - - - - - 5aa7000a by Cheng Shao at 2026-07-15T04:37:08-04:00 compiler: fix redundant AP thunk codegen when not using -ticky-ap-thunk This patch fixes a double negation confusion in !7525 that results in some redundant AP thunk code generation when not using -ticky-ap-thunk. Now, we use `stgToCmmUseStdApThunk` to indicate whether precomputed AP thunks in the RTS should be used, which defaults to `True`, unless `-ticky-ap-thunk` is passed. `-finfo-table-map` now also implies `-ticky-ap-thunk`, since when doing IPE profiling we want the generated AP thunks to be unique. Fixes #27502. ------------------------- Metric Decrease: T3064 ------------------------- Co-authored-by: Codex <codex(a)openai.com> - - - - - d43a7b7a by Brian McKenna at 2026-07-15T20:10:04+02:00 Strip ticks when desugaring bool guards The special `considerAccessible` pattern was broken when compiling with debug info. Compiling with debug info wraps expressions with `SourceNote` ticks, which broke the internals of the `desugarBoolGuard` function. Ticks are now ignored within this function. Fixes #27360 - - - - - ede4b17b by Ben Gamari at 2026-07-15T22:59:53-04:00 base: Display ExceptionContext in WhileHandling's textual description As originally-implemented the implementation for `WhileHandling(displayExceptionAnnotation)` would display the `ExceptionContext` of the exception which it carries (as this was the behavior of `displayException`, in terms of which `displayExceptionAnnotation` was implemented). However, in 284ffab3 the definition of `SomeException(displayException)` was changed to exclude the `ExceptionContext`. This means that `WhileHandling(displayExceptionAnnotation)` fails to describe the provenance of the exception which it captures, greatly limiting its utility. Return the implementation to its originally-specified behavior by implementing `WhileHandling(displayExceptionAnnotation)` in terms of `displayExceptionWithInfo`. Fixes #27456. - - - - - 0f64f348 by Cheng Shao at 2026-07-16T15:41:08+00:00 ci: add missing docker permission workaround in abi-test job - - - - - 660cb239 by Cheng Shao at 2026-07-16T19:37:48+00:00 bindist: Fix make install -j race condition on macos/freebsd This patch fixes make install -j race condition on macos/freebsd. BSD install fails with EEXIST when multiple install processes concurrently create the same prefix directory. So we add an `install_dirs` prerequisite job that sequentially creates the directories for subsequent jobs to work with. Fixes #27499. Co-authored-by: Codex <codex(a)openai.com> - - - - - 08130257 by Cheng Shao at 2026-07-16T19:37:48+00:00 ci: run bindist make install with -j This patch makes the ci scripts run `make install` with `-j` to reduce wall clock time when installing the bindist, see related issue for benchmark numbers. This only affects ghc ci logic, the user-facing default is up to distributors and is still `-j1`. Closes #27029. - - - - - d5ae6906 by Adam Gundry at 2026-07-17T04:57:43-04:00 Mark various language extension flags as deprecated (see #27329) The following language extensions are now deprecated: - AlternativeLayoutRule - AlternativeLayoutRuleTransitional - ParallelArrays - PolymorphicComponents - Rank2Types In addition, the warning `-Walternative-layout-rule-transitional` has been marked as deprecated, as it is emitted only under the deprecated extension `XAlternativeLayoutRuleTransitional`. - - - - - fe3b059c by Andrew Lelechenko at 2026-07-17T04:58:26-04:00 base: re-export GHC.Environment.getFullArgs from System.Environment CLC proposal https://github.com/haskell/core-libraries-committee/issues/431 - - - - - 722236dd by sheaf at 2026-07-18T08:48:31-04:00 Coercion optimisation: avoid double-Sym for InstCo Ticket #27374 pointed out an issue with GHC.Core.Coercion.Opt.optCoercion's handling of InstCo: it contravened (LC2) in Note [The LiftingContext in optCoercion] because it applied the ambient 'sym' to a coercion that was then added to the lifting context substitution. Fixes #27374 Co-authored-by: Simon Jakobi <simon.jakobi(a)gmail.com> - - - - - ff70fc75 by sheaf at 2026-07-18T08:48:31-04:00 Coercion optimisation: avoid exponential behaviour The change to coercion optimisation of 'InstCo' in the previous commit introduces exponential behaviour to the coercion optimiser. To avoid this, this commit provides a way to push in 'Sym' of an already-optimised coercion: GHC.Core.Coercion.Opt.mkDeepSymCo. See Note [Pushing Sym without re-optimising] in GHC.Core.Coercion.Opt. - - - - - dfef27f0 by Duncan Coutts at 2026-07-18T08:49:12-04:00 Move THREADED_RTS-conditional struct members to end of Capability Accessing members of the Capability struct from CMM code rely on accessor macros. (The macros are generated by deriveConstants). These macros have a single definition. This means that the offsets of all struct members must *not* vary based on THREADED_RTS vs !THREADED_RTS. This requires that any struct members that are conditional on THREADED_RTS must occur after the unconditional struct members. Hence we move all the ones that are conditional on THREADED_RTS to the end. Add a deriveConstants entry for the iomgr member of the Capability struct, which was the motivation for this change. Add warning messages to help our future selves. Debugging this took me a couple hours in gdb! - - - - - c254e022 by Duncan Coutts at 2026-07-18T08:49:12-04:00 Make the IOManager API use CapIOManager rather than Capability This makes the API somewhat more self-contained and more consistent. Now the IOManager API and each of the backends takes just the I/O manager structure. Previously we had a bit of a mixture, depending on whether the function needed access to the Capability or just the CapIOManager. We still need access to the cap, so we introduce a back reference to reach the capability, via iomgr->cap. Convert all uses in select and poll backends, but not win32 ones. Convert callers in the scheduler and elsewhere. Also convert the three CMM primops that call IOManager APIs. They just need to use Capability_iomgr(MyCapability()). - - - - - 4f3d8f31 by Duncan Coutts at 2026-07-18T08:49:12-04:00 Split posix/MIO.c out of posix/Signals.c The MIO I/O manager was secretly living inside the Signals file. Now it gets its own file, like any other self-respecting I/O manager. - - - - - 52ce04a9 by Duncan Coutts at 2026-07-18T08:49:12-04:00 Rationalise some scheduler run queue utilities Move them all to the same place in the file. Make some static that were used only internally. Also remove a redundant assignment after calling truncateRunQueue that is already done within truncateRunQueue. - - - - - 75bbdebc by Duncan Coutts at 2026-07-18T08:49:12-04:00 Rename initIOManager{AfterFork} to {re}startIOManager These are more accurate names, since these actions happen after initialisation and are really about starting (or restarting) background threads. - - - - - 724c0517 by Duncan Coutts at 2026-07-18T08:49:12-04:00 Free per-cap I/O managers during shutdown and forkProcess Historically this was not strictly necessary. The select and win32 legacy I/O managers did not maintain any dynamically allocated resources. The new poll one does (an auxillary table), and so this should be freed. After forkProcess, all threads get deleted. This includes threads waiting on I/O or timers. So as of this patch, resetting the I/O manager is just about tidying things up. For example, for the poll I/O manager this will reset the size of the AIOP table (which otherwise grows but never shrinks). In future however the re-initialising will become neeecessary for functionality, since some I/O managers will need to re-initialise wakeup fds that are set CLOEXEC. - - - - - c007d122 by Duncan Coutts at 2026-07-18T08:49:12-04:00 Add a TODO to the MIO I/O manager The direction of travel is to make I/O managers per-capability and have all their state live in the struct CapIOManager. The MIO I/O manager however still has a number of global variables. It's not obvious how handle these globals however. - - - - - b65ab7b3 by Duncan Coutts at 2026-07-18T08:49:12-04:00 Add a FIXME note in the Poll I/O manager - - - - - daf2bd6f by Duncan Coutts at 2026-07-18T08:49:12-04:00 Add missing updateRemembSetPushClosure in poll I/O manager For the non-moving GC. - - - - - e33ca830 by Duncan Coutts at 2026-07-18T08:49:12-04:00 Minor doc improvement to struct StgAsyncIOOp member outcome Mention the enumeration names, as well as their numeric values. The rest of the code uses the enum names. - - - - - 4edd2579 by Duncan Coutts at 2026-07-18T08:49:12-04:00 Minor doc improvements for StgTSOBlockInfo Clarify that certain union members are used only by certain legacy I/O managers. Hopefully we will be able to remove these at some point. - - - - - 536bedbb by Duncan Coutts at 2026-07-18T08:49:12-04:00 Avoid exporting various win32-specific rts symbols The BeginPrivate.h / EndPrivate.h scheme works perfectly well on Windows, but all of the rts/win32/*.h files were not using it. - - - - - 8139b5ac by Duncan Coutts at 2026-07-18T08:49:12-04:00 Remove wakeupIOManager, ioManagerWakeup and setIOManagerWakeupFd We no longer need wakeupIOManager for the threaded RTS case, so we can remove it and the bits only needed to support it. This includes the pipe/eventfd fd shared between the RTS and the in-library I/O manager used for waking up the I/O manager thread. The pipe/eventfd still exists, but it no longer has to be communicated to the RTS, since the RTS no longer needs to use it. So we remove the RTS API export setIOManagerWakeupFd, and remove uses of it within the I/O managers in ghc-internal. - - - - - 74fe7c66 by Duncan Coutts at 2026-07-18T08:49:12-04:00 Add a new interruptIOManager API for the I/O managers It will be used to interrupt awaitCompletedTimeoutsOrIO. Also update the return type and docs for awaitCompletedTimeoutsOrIO to have it return false when it gets interrupted, and have no useful post condition in that case. - - - - - 38792843 by Duncan Coutts at 2026-07-18T08:49:13-04:00 Add interruptIOManager support for select I/O manager Uses the FdWakup mechanism. - - - - - 2f3b00aa by Duncan Coutts at 2026-07-18T08:49:13-04:00 Add interruptIOManager support for poll I/O manager Uses the FdWakup mechanism. A quirk we have to cope with is that we now need to poll one more fd -- the wakeup_fd_r -- but this fd has no corresponding entry in the aiop_table. This is awkward since we have set up our aiop_poll_table to be an auxilliary table with matching indicies. The solution this patch uses (and described in the comments) is to have two tables: struct pollfd *aiop_poll_table, *full_poll_table; and to have the aiop_poll_table alias the tail of the full_poll_table. The head entry in the full_poll_table is the extra fd. So we poll the full_poll_table, while the aiop_poll_table still has matching indicies with the aiop_table. Hurrah for C aliasing rules. - - - - - cee50131 by Duncan Coutts at 2026-07-18T08:49:13-04:00 Add interruptIOManager support for win32 legacy I/O manager And remove unused related helper resetAbandonRequestWait. It is not called because the event is created in auto-reset mode, so never needs to be reset manually. - - - - - cf453143 by Duncan Coutts at 2026-07-18T08:49:13-04:00 Note lack of interruptIOManager support for WinIO I/O manager Though there's a plausible design, we can't sanely test it at the moment due to related WinIO bugs. Filed as issue #27403. - - - - - 1b74a0ad by Duncan Coutts at 2026-07-18T08:49:13-04:00 Be more explicit about enum IOReadOrWrite values, and type within cmm Belt and braces. - - - - - b388d093 by Brian McKenna at 2026-07-18T17:51:50-04:00 Ignore ticks in the pattern-match term oracle The term-oracle in the pattern-match checker is keyed by a canonical form of the scrutinee, computed by `makeDictsCoherent`. That canonical form was tick-sensitive: two occurrences of an otherwise identical expression that happened to carry different ticks were treated as distinct values, breaking long-distance information. This shows up in practice under `-finfo-table-map`, because the desugarer wraps every record-selector use site in a `SourceNote` carrying that site's span. For example: data Box = Box { unBox :: Maybe Int } f b = case unBox b of Nothing -> 0 Just _ -> let Just x = unBox b in x The two `unBox b` expressionss carry different SourceNote spans, the pattern-match checker sees them as different, the long-distance information from the outer `Just _` branch never reaches the let-pattern, and `Just x = unBox b` is wrongly reported as non-exhaustive. We now strip all ticks in `makeDictsCoherent`. This is documented as Wrinkle (UD1) of Note [Unique dictionaries in the TmOracle CoreMap]. Fixes #27314 - - - - - c23e1acb by Mrjtjmn at 2026-07-18T17:52:45-04:00 Add explanations for unsolved Typeable constraints This commit adds explanations for unsolved 'Typeable' constraints. GHC will now provide additional explanations for an unsolved constraint of the form 'Typeable ty', explain why GHC did not solve Typeable constraint. e.g.: - 'ty' is a polymorphic type (e.g. forall a. a -> a) - 'ty' is a qualified type (e.g. Eq Int => Int) - 'ty' is an unboxed sum type - 'ty' is an unreduced type family application - 'ty' whose kind is not typeable Fixes #26532 - - - - - cbef021e by Artem Pelenitsyn at 2026-07-19T07:49:55-04:00 ghc-internal: Lock.hs: fix typo and indentation - - - - - 42918646 by Duncan Coutts at 2026-07-19T07:50:36-04:00 Fix failing test GcStaticPointers for non-moving GC Minor mistake in asserting something before checking for that same thing. Specifically, Bdescr asserts HEAP_ALLOCED_GC, but Bdescr was being used prior to a guard that checks HEAP_ALLOCED_GC. The solution is just to move the use of Bdescr after the guard. Thanks to Simon Jakobi for identifying the problem. - - - - - c2f6dcd4 by Sasha Bogicevic at 2026-07-20T10:31:56+02:00 Improve error messages for invalid record wildcards Record wildcard hints are now shown in more contexts and include constructor arity; matching with `..` on a fieldless constructor now produces a dedicated error message. Fixes #21101 - - - - - 4c02e76b by Duncan Coutts at 2026-07-21T10:37:21-04:00 Mark test T27105 as fragile, citing issue #27522 Scheduler fairness is fine, except when it isn't. And it isn't on CI machines surprisingly often! See the issue for details. - - - - - 43dd2b15 by Recursion Ninja at 2026-07-21T17:09:53-04:00 Resolving many TTG related orphan type-class instances This is part a technical debt removal effort made possible now that separating out the AST via TTG has come to a close. As the AST in 'L.H.S' has been incrementally separated from the GHC internals, there are many accumulated orphan instance of 'Binary', 'NFData', 'Outputable', and 'Uniquable'. The orphan instance of data-types from within 'L.H.S' have had their orphan instances moved to either: 1. The module which defines the data-type 2. The module which defines the type-class; i.e. moving an orphan 'Binary' instance to 'GHC.Utils.Binary' Orphan instances resolved (37): | Data-type | Resolved instance(s) | Former orphan module(s) | | -------------------- | -------------------------- | ------------------------- | | Role | Binary, NFData, Outputable | GHC.Core.Coercion.Axiom | | SrcStrictness | Binary, NFData, Outputable | GHC.Core.DataCon | | SrcUnpackedness | Binary, NFData, Outputable | GHC.Core.DataCon | | Fixity | Binary, Outputable | GHC.Hs.Basic | | FixityDirection | Binary, Outputable | GHC.Hs.Basic | | LexicalFixity | Outputable | GHC.Hs.Basic | | CCallTarget | NFData | GHC.Hs.Decls.Foreign | | CType | NFData | GHC.Hs.Decls.Foreign | | Header | NFData | GHC.Hs.Decls.Foreign | | OverlapMode | Binary, NFData | GHC.Hs.Decls.Overlap | | WithHsDocIdentifiers | NFData, Outputable | GHC.Hs.Doc | | HsDocString | NFData | GHC.Hs.DocString | | HsDocStringChunk | Binary, Outputable | GHC.Hs.DocString | | HsDocStringDecorator | Binary, Outputable | GHC.Hs.DocString | | NamespaceSpecifier | Outputable | GHC.Hs.ImpExp | | ForAllTyFlag | Binary, NFData, Outputable | GHC.Hs.Specificity | | Specificity | Binary, NFData | GHC.Hs.Specificity | | PromotionFlag | Binary, Outputable | GHC.Types.Basic | | FieldLabelString | Outputable, Uniquable | GHC.Types.FieldLabel | | InlinePragma | Binary | GHC.Types.InlinePragma | ------------------------- Metric Decrease: hard_hole_fits ------------------------- Closes #21262, #27469 - - - - - ab9ab895 by Cheng Shao at 2026-07-21T17:10:53-04:00 rts: always use StgInt to represent cost center id Currently cost center id is modeled as `Int` and it should be `StgInt` uniformly in the RTS, hence this patch. Fixes #27524. - - - - - 94d8f83b by Cheng Shao at 2026-07-22T11:30:40-04:00 hadrian: clean up stale cabal package flags in the tree This patch cleans up stale cabal package flags in the tree and related hadrian/autoconf logic. Closes #27474. Co-authored-by: Codex <codex(a)openai.com> - - - - - 0bf1d8c9 by Sasha Bogicevic at 2026-07-22T11:31:21-04:00 parser: don't suggest ImportQualifiedPost when it is already enabled -Wprepositive-qualified-module unconditionally attached a hint to enable ImportQualifiedPost, even when the extension was already on (as it is by default under GHC2021). Record the extension's state in the PsWarnImportPreQualified diagnostic and drop the hint when it is already enabled. Fixes #27380 - - - - - 700a1dd1 by Simon Jakobi at 2026-07-23T11:21:20-04:00 ci: Reduce lint job setup costs Avoid fetching unnecessary history and submodules for lightweight lint jobs. Run changelog validation without Hadrian. Because the lint-author job is now based on the .lint template directly, we enhance it to allow Git to read from the runner-owned checkouts, In the previously used .lint-params template, this permissions issue was addressed via `chown`. Closes #27521. Assisted-by: gpt-5.6-sol via Codex CLI - - - - - 26a44fb0 by ARATA Mizuki at 2026-07-23T11:22:10-04:00 testsuite: Fix memory issues of doublex2_* and simd010 doublex2_* had reads from uninitialized memory. simd010 had out-of-bounds array access. Fixes #27544 - - - - - 4d798b17 by Duncan Coutts at 2026-07-23T17:26:18-04:00 Eliminate STM_AWOKEN It was used as nullary closure for the block_info.closure in the case of a thread being awoken after an STM transaction. However, while it was written, it was never read, so contributed nothing to the behaviour. Furthermore, in the only place it was set (in tryWakeupThread) the why_blocked was immediately overwritten by the NotBlocked status, and the block_info was updated accordingly (by appendToRunQueue). So it didn't even serve a purpose of clarifying an intermediate state, there really was no such intermediate state. Cleaning this up will allow the BlockedOnSTM case to follow the same pattern as the other why_blocked cases that do not use the block_info, and in turn this reduces the number of different categories. - - - - - e1cece79 by Duncan Coutts at 2026-07-23T17:26:18-04:00 Document that eventlog thread stop code ThreadBlocked is no longer used It has not been used since GHC 7.0.x (2011). In 7.2 all the BlockedOn* codes were added, and these were and are used instead of ThreadBlocked. - - - - - 795db115 by Duncan Coutts at 2026-07-23T17:26:18-04:00 Add a proper mapping to eventlog external thread stop status That is the mapping from rts-internal codes, to the coes used in the status field in the eventlog EVENT_STOP_THREAD event. See issue #9003 for what goes wrong when we mess this up. In that ticket, people note that we should really not require the internal tso->why_blocked codes to leak into the external eventlog thread stop codes. The same principle applies to the StgThreadReturnCode. This change properly separates them, and explicitly maps between them using a pair of (compact, constant) tables. These tables are pretty small (with no alignment constraints) and will soon shrink so it seems a sensible tradeoff. We also introduce and use proper EVENT_STOP_THREAD constants in the event log format header. Previously there was not specification in the code for these (only in the docs): the values were encoded into the conversion code. This will allow us to renumber the internal why_blockd codes without breaking the eventlog output. - - - - - 6f1c8efa by Duncan Coutts at 2026-07-23T17:26:18-04:00 Remove unused tso->block_info.wakeup member Presumably it was used once, but not now. - - - - - 740b88a9 by Duncan Coutts at 2026-07-23T17:26:18-04:00 Document StgTSOBlockInfo to say what cases use what members In principle, tso->why_blocked is the tag for the StgTSOBlockInfo union, so we should be able to say for each union member the why_blocked cases that use that member. - - - - - 5b92eae2 by Duncan Coutts at 2026-07-23T17:26:18-04:00 Add a tso->block_info.mvar member and use it in preference to the generic block_info.closure union member, with casts. The plan is that when we know what case we're in (via tso->why_blocked) then we can always access the correct union member, and so we will only need to access block_info.closure for generic cases where we don't know or don't care. - - - - - d931715f by Duncan Coutts at 2026-07-23T17:26:18-04:00 Add a tso->block_info.unused member and use it in preference to the generic block_info.closure union member, with casts. The plan is that when we know what case we're in (via tso->why_blocked) then we can always access the correct union member, and so we will only need to access block_info.closure for generic cases where we don't know or don't care. - - - - - 47e28ebb by Duncan Coutts at 2026-07-23T17:26:18-04:00 Avoid storing to tso->block_info.closure In one case we can use a specific union member (.prev) instead. In several cases the stores were in fact redundant because of subsequent overwrites. In scavengeTSO we replace setting tso->block_info.closure to a valid closure, with an assertion that the block_info.unused is already set to END_TSO_QUEUE which is a valid (static) closure. - - - - - 96e4749d by Duncan Coutts at 2026-07-23T17:26:18-04:00 Renumber the tso->why_blocked constants We can do this now because we have separated the internal values from the external ones used in the eventlog. This lets us put them back into a deliberate order and consolodate some gaps. More importantly, it is a prepation for a slightly more sophisticated encoding. - - - - - 8f62661c by Duncan Coutts at 2026-07-23T17:26:18-04:00 Define constants for the existing stg_threadStatuszh return codes The stg_threadStatuszh reuses the internal tso->why_blocked codes but also extends them with a couple previously magic values. This is awkward since we need to know what those magic values are so we don't accidentally use those values to mean something else. By pulling a definition up to where the why_blocked codes are defined we will be able to avoid mistakenly assining those codes some meaning (or just changing the BlockedThreadComplete, BlockedThreadKilled code if necessary). - - - - - 42c69ae2 by Duncan Coutts at 2026-07-23T17:26:18-04:00 Extend the tso->why_blocked encoding to indicate block_info closures We use some bit tricks to cheaply and generically test if a tso->why_blocked tag implies that the corresponding tso->block_info will contain a non-trivial valid closure (i.e. not just block_info.unused set to END_TSO_QUEUE). In particular we arrange for most why_blocked values to naturally have a distinguishing bit, but for the BlockedOn{Read,Write,Delay} cases, they can come in either non-closure or closure forms. We allow an additional bit to distinguish these cases. The non-closure forms are only from legacy I/O managers: select and win32-legacy. So this extra bit mechanism will be able to be retired once the legacy I/O managers are themselves retired. This means in a few places we need to untag the why_blocked value before inspecting it, but in most places we do not. - - - - - 7c64632b by Duncan Coutts at 2026-07-23T17:26:18-04:00 Use BlockInfoForceNonClosure in the select I/O manager - - - - - 8fd7104a by Duncan Coutts at 2026-07-23T17:26:18-04:00 Use BlockInfoForceNonClosure in the win32-legacy I/O manager for the BlockedOn{Read,Write} since these use the non-heap allocated StgAsyncIOResult. - - - - - e0da603b by Duncan Coutts at 2026-07-23T17:26:18-04:00 Enforce the why_blocked and block_info rules in checkTSO We now check the cases wher IsBlockInfoClosure should hold, the cases that are supposed to use block_info.unused == END_TSO_QUEUE, and which cases are allowed to use BlockInfoForceNonClosure. This partially enforces the use of why_blocked as a tag for the block_info union. We could be stricter and check for the correct expected info table for the closure cases. - - - - - 1dd0f381 by Duncan Coutts at 2026-07-23T17:26:18-04:00 Use IsBlockInfoClosure to simplify several tests In GC and generic traversal we need to know if we should look at the block_info.closure or not. Now we can do just that using a cheap bit test on the why_blocked tag. This fixes issue 26717, where the problem was that some GC modes did not know when to look at block_info.closure, because the poll I/O manager uses a closure for BlockedOn{Read,Write} while the select I/O manager uses a non-closure. Now this information is in the why_blocked tag itself. - - - - - 7a00ffbc by Duncan Coutts at 2026-07-23T17:26:18-04:00 Remove the now-unused scavengeTSOIOManager The GC no longer has to delegate to the I/O manager, since it can use IsBlockInfoClosure to decide things itself. - - - - - 522a481f by Duncan Coutts at 2026-07-23T17:26:18-04:00 Remove duplicate assertion - - - - - 0874d965 by Duncan Coutts at 2026-07-23T17:26:18-04:00 Follow atomic access rules more consistently for tso->why_blocked The rule is this: store block_info *before* why_blocked store why_blocked using store release load why_blocked using load acquire load block_info *after* why_blocked This is a an atomic store release / load acquire pair and (if the reads are in a separate thread to the writes, and the read receives the value stored) then this guarantees a full "happens before" relationship of these stores and loads. In some cases, we do not need a full load acquire, because we don't read the block_info at all and so do not need any ordering. In this case we just need an atomic relaxed load. This was being followed in most places, but not all. If there's good reason in any case that we don't need atomic access, then we should document that in a comment. In the absence of that I think it's easier to follow the rule everywhere. - - - - - 8f0bdbe1 by Duncan Coutts at 2026-07-23T17:26:19-04:00 Add a changelog entry - - - - - 4fdfe757 by Alan Zimmerman at 2026-07-23T17:27:06-04:00 EPA: Keep decls together in ClassDecl Similar to 1718230f4d3d19d8c49c0e5d496cb0fb6f399528 for HsValBindsLR, this commit updates ClassDecl so that it no longer splits out the assorted `LHsDecl GhcPs` until the renamer. It does this by inserting a type family (separate from the classic TTG one) for this. So data TyClDecl ... | ClassDecl { ... tcdDecls :: XClassDecls pass with type instance XClassDecls GhcPs = [LHsDecl GhcPs] type instance XClassDecls GhcRn = ClassDeclX GhcRn type instance XClassDecls GhcTc = ClassDeclX GhcTc data ClassDeclX pass = ClassDeclX { tcdSigs :: [LSig pass], -- ^ Methods' signatures tcdMeths :: LHsBinds pass, -- ^ Default methods tcdATs :: [LFamilyDecl pass], -- ^ Associated types; tcdATDefs :: [LTyFamDefltDecl pass], -- ^ Associated type defaults tcdDocs :: [LDocDecl pass] -- ^ Haddock docs } - - - - - f586c885 by Simon Jakobi at 2026-07-24T18:05:00-04:00 ci: Use shallow submodule clones by default Limit submodule clones to depth one to reduce CI checkout costs. Keep fetching full submodule history for the submodule lint jobs, which inspect commits across a range. Assisted-by: gpt-5.6-sol via Codex CLI - - - - - 306120d2 by Duncan Coutts at 2026-07-24T18:05:43-04:00 Fix flaky test T3994 on FreeBSD On current FreeBSD versions, calling getpgid on a zombie process fails. In T3994, if we're really unlucky with delays and scheduling then we can end up in exactly that situation. Just catch that specific exception and ignore it. It's rare, and not our fault. - - - - - 7b116a0b by Cheng Shao at 2026-07-24T18:06:24-04:00 ci: add missing workaround for docker permissions in lint jobs Some lint jobs use ci-images with default user `ghc`, and the gitlab ci docker executor requires the `sudo chown` workaround to fix workspace directory permission issue. This patch adds the missing workarounds for the lint jobs. Fixes #27554. Co-authored-by: Codex <codex(a)openai.com> - - - - - 815149f3 by Andrzej Rybczak at 2026-07-25T15:06:43+00:00 Add -Wdefaulted-callstack Adds a new warning, -Wdefaulted-callstack, which warns when an implicit CallStack parameter is defaulted to the empty stack. In particular, this includes call sites where a function with a HasCallStack constraint is called from a definition that does *not* provide one. At such call sites the call stack is cut off and does not include the enclosing definition's callers, which can be a source of surprise if the user wants complete call stacks. Closes #27077. - - - - - f6f2343f by Zubin Duggal at 2026-07-25T17:40:51-04:00 UniqueDFM: alter should preserve insertion order Before it always inserting new elements at the end. This is problematic because instances get inserted into the map with `alterF`, which can change ordering of how instances are printed with `:info` depending on the order in which we consult interfaces I expect `alter id k = id` and `alter (fmap f) k = adjust f k`. Moving keys to the end breaks that (`adjust` already preserves position). Fixes #27532 - - - - - 49120a8e by Simon Jakobi at 2026-07-27T14:18:46+02:00 testsuite: Colorize the test summary, also in CI The summary headings were plain, and SUMMARY was colored unconditionally, so the escapes also ended up in the file written by --summary-file. Color is now decided per output sink via term_color.colored_if; see the comments in term_color. CI logs are not a tty, but GitLab's log viewer renders ANSI colors, so add --force-colors and pass it in .gitlab/ci.sh. That also fixes the RUNTEST_ARGS assignment for --ignore-perf-failures, which used array syntax although every use site expands the variable as a string. Assisted-by: Claude Opus 5 - - - - - a38f657e by Simon Jakobi at 2026-07-27T14:18:46+02:00 testsuite: Repeat unexpected failure output in the summary Finding out why a test failed meant scrolling back through a possibly very long log to the point where the test ran. The summary now repeats the captured output of unexpected failures, before the statistics, so the interesting part is at the end of the log (#16720). Output is bounded per stream and skipped altogether beyond MAX_SUMMARY_OUTPUT_TESTS failures, pointing at the JUnit file instead; tests failing identically in several ways share one block. Test results now report a source-relative directory, which is stable regardless of where the run was started from. Assisted-by: Claude Opus 5 - - - - - 456 changed files: - .gitignore - .gitlab-ci.yml - .gitlab/ci.sh - .gitlab/merge_request_templates/Default.md - .gitlab/rel_eng/mk-ghcup-metadata/mk_ghcup_metadata.py - + changelog.d/21101 - + changelog.d/27380 - + changelog.d/27532 - + changelog.d/T21628 - + changelog.d/T26532 - + changelog.d/T26716 - + changelog.d/T27123.md - + changelog.d/T27314.md - + changelog.d/T27329 - + changelog.d/T27360 - + changelog.d/T27374 - + changelog.d/T27456 - + changelog.d/fix-cmm-atomic-load-store - + changelog.d/fix-make-install-j - + changelog.d/fix-peekitbl-no-tntc - + changelog.d/fix-use-std-ap-thunk - + changelog.d/inter-module-far-jumps-aarch64-default - + changelog.d/warn-defaulted-callstack - compiler/GHC/Builtin/Types/Prim.hs - compiler/GHC/Builtin/Utils.hs - compiler/GHC/ByteCode/Breakpoints.hs - compiler/GHC/ByteCode/Types.hs - compiler/GHC/Cmm/CLabel.hs - compiler/GHC/Cmm/Parser.y - compiler/GHC/Core/Coercion/Axiom.hs - compiler/GHC/Core/Coercion/Opt.hs - compiler/GHC/Core/DataCon.hs - compiler/GHC/Core/Ppr.hs - compiler/GHC/Core/TyCo/Ppr.hs - compiler/GHC/Core/TyCo/Rep.hs - compiler/GHC/Core/TyCon.hs - compiler/GHC/Data/FastString.hs - compiler/GHC/Data/StringBuffer.hs - compiler/GHC/Driver/Backend.hs - compiler/GHC/Driver/CodeOutput.hs - compiler/GHC/Driver/Config/StgToCmm.hs - compiler/GHC/Driver/DynFlags.hs - compiler/GHC/Driver/Errors/Ppr.hs - compiler/GHC/Driver/Flags.hs - compiler/GHC/Driver/Main/Compile.hs - compiler/GHC/Driver/Main/Hsc.hs - compiler/GHC/Driver/Main/Passes.hs - compiler/GHC/Driver/Pipeline.hs - compiler/GHC/Driver/Session.hs - compiler/GHC/Hs/Basic.hs - compiler/GHC/Hs/Binds.hs - compiler/GHC/Hs/Decls.hs - compiler/GHC/Hs/Decls/Overlap.hs - compiler/GHC/Hs/Doc.hs - compiler/GHC/Hs/DocString.hs - compiler/GHC/Hs/Dump.hs - compiler/GHC/Hs/Expr.hs - compiler/GHC/Hs/ImpExp.hs - compiler/GHC/Hs/Instances.hs - compiler/GHC/Hs/Lit.hs - − compiler/GHC/Hs/Specificity.hs - compiler/GHC/Hs/Stats.hs - compiler/GHC/Hs/Type.hs - compiler/GHC/Hs/Utils.hs - compiler/GHC/HsToCore.hs - compiler/GHC/HsToCore/Breakpoints.hs - + compiler/GHC/HsToCore/Breakpoints/Types.hs - compiler/GHC/HsToCore/Docs.hs - compiler/GHC/HsToCore/Errors/Types.hs - compiler/GHC/HsToCore/Expr.hs - compiler/GHC/HsToCore/Foreign/C.hs - compiler/GHC/HsToCore/Foreign/JavaScript.hs - compiler/GHC/HsToCore/Foreign/Wasm.hs - compiler/GHC/HsToCore/Match.hs - compiler/GHC/HsToCore/Match/Literal.hs - compiler/GHC/HsToCore/Pmc/Desugar.hs - compiler/GHC/HsToCore/Pmc/Solver.hs - compiler/GHC/HsToCore/Pmc/Solver/Types.hs - compiler/GHC/HsToCore/Quote.hs - compiler/GHC/HsToCore/Ticks.hs - compiler/GHC/Iface/Ext/Ast.hs - compiler/GHC/Iface/Load.hs - compiler/GHC/Iface/Make.hs - compiler/GHC/Iface/Recomp.hs - compiler/GHC/Iface/Syntax.hs - compiler/GHC/Parser.y - compiler/GHC/Parser/Annotation.hs - compiler/GHC/Parser/Errors/Ppr.hs - compiler/GHC/Parser/Errors/Types.hs - compiler/GHC/Parser/HaddockLex.x - compiler/GHC/Parser/Lexer.x - compiler/GHC/Parser/PostProcess.hs - compiler/GHC/Parser/PostProcess/Haddock.hs - compiler/GHC/Platform/Ways.hs - compiler/GHC/Rename/Bind.hs - compiler/GHC/Rename/Env.hs - compiler/GHC/Rename/Expr.hs - compiler/GHC/Rename/HsType.hs - compiler/GHC/Rename/Module.hs - compiler/GHC/Rename/Names.hs - compiler/GHC/Rename/Pat.hs - compiler/GHC/Rename/Splice.hs - compiler/GHC/Rename/Utils.hs - compiler/GHC/Runtime/Eval.hs - compiler/GHC/StgToByteCode.hs - compiler/GHC/StgToCmm/Bind.hs - compiler/GHC/StgToCmm/Config.hs - compiler/GHC/StgToCmm/Foreign.hs - compiler/GHC/StgToCmm/Prim.hs - compiler/GHC/StgToJS/FFI.hs - compiler/GHC/Tc/Deriv.hs - compiler/GHC/Tc/Deriv/Generate.hs - compiler/GHC/Tc/Deriv/Generics.hs - compiler/GHC/Tc/Errors.hs - compiler/GHC/Tc/Errors/Ppr.hs - compiler/GHC/Tc/Errors/Types.hs - compiler/GHC/Tc/Gen/Bind.hs - compiler/GHC/Tc/Gen/Expr.hs - compiler/GHC/Tc/Gen/Head.hs - compiler/GHC/Tc/Gen/HsType.hs - compiler/GHC/Tc/Gen/Pat.hs - compiler/GHC/Tc/Gen/Sig.hs - compiler/GHC/Tc/Gen/Splice.hs - compiler/GHC/Tc/Instance/Class.hs - compiler/GHC/Tc/Instance/Typeable.hs - compiler/GHC/Tc/Solver/Default.hs - compiler/GHC/Tc/Solver/Dict.hs - compiler/GHC/Tc/TyCl.hs - compiler/GHC/Tc/TyCl/Class.hs - compiler/GHC/Tc/TyCl/Utils.hs - compiler/GHC/Tc/Types/Evidence.hs - compiler/GHC/Tc/Types/Origin.hs - compiler/GHC/Tc/Types/Rank.hs - compiler/GHC/Tc/Utils/Unify.hs - compiler/GHC/Tc/Validity.hs - compiler/GHC/ThToHs.hs - compiler/GHC/Types/Basic.hs - compiler/GHC/Types/Error.hs - compiler/GHC/Types/Error/Codes.hs - compiler/GHC/Types/FieldLabel.hs - compiler/GHC/Types/Fixity.hs - compiler/GHC/Types/ForeignCall.hs - compiler/GHC/Types/GREInfo.hs - compiler/GHC/Types/Hint.hs - compiler/GHC/Types/Hint/Ppr.hs - compiler/GHC/Types/InlinePragma.hs - compiler/GHC/Types/Literal.hs - compiler/GHC/Types/Unique.hs - compiler/GHC/Types/Unique/DFM.hs - compiler/GHC/Types/Var.hs - compiler/GHC/Unit/Module/ModGuts.hs - compiler/GHC/Unit/Module/ModIface.hs - compiler/GHC/Unit/Module/Warnings.hs - compiler/GHC/Unit/Module/WholeCoreBindings.hs - compiler/GHC/Utils/Binary.hs - compiler/GHC/Utils/Outputable.hs - compiler/Language/Haskell/Syntax/Basic.hs - compiler/Language/Haskell/Syntax/Binds.hs - compiler/Language/Haskell/Syntax/Decls.hs - compiler/Language/Haskell/Syntax/Decls/Foreign.hs - compiler/Language/Haskell/Syntax/Doc.hs - compiler/Language/Haskell/Syntax/Expr.hs - compiler/Language/Haskell/Syntax/Extension.hs - compiler/Language/Haskell/Syntax/ImpExp.hs - compiler/Language/Haskell/Syntax/Lit.hs - compiler/Language/Haskell/Syntax/Module/Name.hs - compiler/Language/Haskell/Syntax/Specificity.hs - + compiler/Language/Haskell/Syntax/Text.hs - compiler/Language/Haskell/Syntax/Type.hs - compiler/ghc.cabal.in - configure.ac - distrib/configure.ac.in - docs/users_guide/eventlog-formats.rst - docs/users_guide/expected-undocumented-flags.txt - docs/users_guide/exts/rank_polymorphism.rst - docs/users_guide/exts/static_pointers.rst - docs/users_guide/using-optimisation.rst - docs/users_guide/using-warnings.rst - ghc/GHCi/UI.hs - hadrian/bindist/Makefile - hadrian/cabal.project - hadrian/cfg/system.config.host.in - hadrian/cfg/system.config.target.in - hadrian/src/Oracles/Flag.hs - hadrian/src/Rules.hs - hadrian/src/Rules/BinaryDist.hs - hadrian/src/Rules/Generate.hs - hadrian/src/Rules/Test.hs - hadrian/src/Settings/Packages.hs - libraries/base/changelog.md - libraries/base/src/GHC/Stack.hs - libraries/base/src/System/Environment.hs - libraries/base/tests/T15349.stderr - libraries/ghc-boot/GHC/Data/ShortText.hs - libraries/ghc-heap/GHC/Exts/Heap/FFIClosures_ProfilingDisabled.hsc - libraries/ghc-heap/GHC/Exts/Heap/FFIClosures_ProfilingEnabled.hsc - + libraries/ghc-heap/tests/T27465.hs - + libraries/ghc-heap/tests/T27465.stdout - libraries/ghc-heap/tests/all.T - libraries/ghc-internal/ghc-internal.cabal.in - libraries/ghc-internal/src/GHC/Internal/Conc/Sync.hs - libraries/ghc-internal/src/GHC/Internal/Event/Control.hs - libraries/ghc-internal/src/GHC/Internal/Event/Manager.hs - libraries/ghc-internal/src/GHC/Internal/Event/TimerManager.hs - libraries/ghc-internal/src/GHC/Internal/Exception/Type.hs - libraries/ghc-internal/src/GHC/Internal/Heap/InfoTable.hsc - libraries/ghc-internal/src/GHC/Internal/Heap/InfoTableProf.hsc - libraries/ghc-internal/src/GHC/Internal/IO/Handle/Lock.hs - libraries/ghc-internal/src/GHC/Internal/Stack.hs - libraries/ghc-internal/tests/backtraces/T14532b.stdout - m4/fp_check_pthreads.m4 - nofib - rts/Apply.cmm - rts/Capability.c - rts/Capability.h - rts/ContinuationOps.cmm - rts/IOManager.c - rts/IOManager.h - rts/IOManagerInternals.h - rts/Messages.c - rts/PrimOps.cmm - rts/Profiling.c - rts/RaiseAsync.c - rts/RaiseAsync.h - rts/RtsStartup.c - rts/RtsSymbols.c - rts/STM.c - rts/Schedule.c - rts/Schedule.h - rts/StgMiscClosures.cmm - rts/Threads.c - rts/Trace.c - rts/Trace.h - rts/TraverseHeap.c - rts/eventlog/EventLog.c - rts/eventlog/EventLog.h - rts/include/Cmm.h - rts/include/rts/Constants.h - rts/include/rts/EventLogFormat.h - rts/include/rts/IOInterface.h - rts/include/rts/storage/Closures.h - rts/include/rts/storage/TSO.h - rts/include/stg/MiscClosures.h - rts/posix/FdWakeup.h - + rts/posix/MIO.c - + rts/posix/MIO.h - rts/posix/Poll.c - rts/posix/Poll.h - rts/posix/Select.c - rts/posix/Select.h - rts/posix/Signals.c - rts/posix/Signals.h - rts/posix/Timeout.c - rts/posix/Timeout.h - rts/rts.cabal - rts/sm/Compact.c - rts/sm/NonMovingMark.c - rts/sm/Sanity.c - rts/sm/Scav.c - rts/win32/AsyncMIO.c - rts/win32/AsyncMIO.h - rts/win32/AsyncWinIO.h - rts/win32/AwaitEvent.c - rts/win32/AwaitEvent.h - rts/win32/ConsoleHandler.h - rts/win32/MIOManager.h - rts/win32/ThrIOManager.h - rts/win32/WorkQueue.h - rts/win32/veh_excn.h - testsuite/driver/junit.py - testsuite/driver/perf_notes.py - testsuite/driver/runtests.py - testsuite/driver/term_color.py - testsuite/driver/testglobals.py - testsuite/driver/testlib.py - testsuite/driver/testutil.py - testsuite/tests/backpack/should_compile/T13149.bkp - testsuite/tests/cmm/should_run/AtomicFetch.hs - testsuite/tests/cmm/should_run/AtomicFetch_cmm.cmm - testsuite/tests/codeGen/should_compile/T25177.stderr - testsuite/tests/codeGen/should_run/cgrun025.stderr - testsuite/tests/concurrent/should_run/T27105.hs - testsuite/tests/concurrent/should_run/all.T - + testsuite/tests/corelint/T27374.hs - testsuite/tests/corelint/all.T - testsuite/tests/count-deps/CountDepsAst.stdout - testsuite/tests/count-deps/CountDepsParser.stdout - testsuite/tests/deSugar/should_fail/all.T - testsuite/tests/determinism/determ017/A.hs - testsuite/tests/exceptions/T26759.stderr - testsuite/tests/ghc-api/T25121_status.stdout - testsuite/tests/ghc-api/annotations-literals/parsed.hs - testsuite/tests/ghc-api/exactprint/T22919.stderr - testsuite/tests/ghc-api/exactprint/Test20239.stderr - testsuite/tests/ghc-api/exactprint/ZeroWidthSemi.stderr - testsuite/tests/ghc-e/should_fail/T18441fail7.stderr - testsuite/tests/ghci/T16793/T16793.stdout - testsuite/tests/ghci/T18060/T18060.stdout - + testsuite/tests/ghci/T27532/Makefile - + testsuite/tests/ghci/T27532/T27532.stdout - + testsuite/tests/ghci/T27532/T27532j4.stdout - + testsuite/tests/ghci/T27532/a.script - + testsuite/tests/ghci/T27532/all.T - + testsuite/tests/ghci/T27532/b.script - + testsuite/tests/ghci/T27532/genT27532Modules - testsuite/tests/ghci/scripts/ListTuplePunsPpr.stdout - testsuite/tests/ghci/scripts/T12005.script - testsuite/tests/ghci/scripts/T4175.stdout - testsuite/tests/ghci/scripts/T8469.stdout - testsuite/tests/ghci/scripts/T8535.stdout - testsuite/tests/ghci/scripts/T9881.stdout - testsuite/tests/ghci/scripts/all.T - + testsuite/tests/ghci/scripts/bytecodeIPE.hs - + testsuite/tests/ghci/scripts/bytecodeIPE.script - + testsuite/tests/ghci/scripts/bytecodeIPE.stdout - testsuite/tests/ghci/scripts/ghci020.stdout - testsuite/tests/ghci/scripts/ghci064.stdout - testsuite/tests/ghci/should_run/Makefile - testsuite/tests/ghci/should_run/T10145.stdout - testsuite/tests/ghci/should_run/T18594.stdout - + testsuite/tests/ghci/should_run/T27287.hs - + testsuite/tests/ghci/should_run/T27287.stdout - testsuite/tests/ghci/should_run/all.T - testsuite/tests/haddock/haddock_examples/haddock.Test.stderr - testsuite/tests/haddock/perf/Fold.hs - testsuite/tests/haddock/should_compile_flag_haddock/T17544.stderr - testsuite/tests/haddock/should_compile_flag_haddock/T17544_kw.stderr - testsuite/tests/haddock/should_compile_flag_haddock/T24221.stderr - testsuite/tests/indexed-types/should_fail/T7354.hs - testsuite/tests/interface-stability/base-exports.stdout - testsuite/tests/interface-stability/base-exports.stdout-javascript-unknown-ghcjs - testsuite/tests/interface-stability/base-exports.stdout-mingw32 - testsuite/tests/layout/layout001.stdout - testsuite/tests/layout/layout002.stdout - testsuite/tests/layout/layout003.stdout - testsuite/tests/layout/layout004.stdout - testsuite/tests/layout/layout005.stdout - testsuite/tests/layout/layout006.stdout - testsuite/tests/layout/layout007.stdout - testsuite/tests/layout/layout008.stdout - testsuite/tests/layout/layout009.stdout - testsuite/tests/linear/should_compile/T1735Min.hs - testsuite/tests/mdo/should_fail/mdofail006.stderr - + testsuite/tests/module/T27380.hs - + testsuite/tests/module/T27380.stderr - testsuite/tests/module/all.T - testsuite/tests/module/mod184.stderr - testsuite/tests/module/mod185.stderr - testsuite/tests/numeric/should_compile/T15547.stderr - testsuite/tests/parser/should_compile/DumpParsedAst.stderr - testsuite/tests/parser/should_compile/DumpParsedAstComments.stderr - testsuite/tests/parser/should_compile/DumpRenamedAst.stderr - testsuite/tests/parser/should_compile/DumpSemis.stderr - testsuite/tests/parser/should_compile/DumpTypecheckedAst.stderr - testsuite/tests/parser/should_compile/KindSigs.stderr - + testsuite/tests/parser/should_compile/T13087.stderr - testsuite/tests/parser/should_compile/T14189.stderr - testsuite/tests/parser/should_compile/T15323.stderr - testsuite/tests/parser/should_compile/T20452.stderr - testsuite/tests/parser/should_compile/T20718.stderr - testsuite/tests/parser/should_compile/T20718b.stderr - testsuite/tests/parser/should_compile/T20846.stderr - testsuite/tests/parser/should_compile/T23315/T23315.stderr - testsuite/tests/parser/should_fail/T8431.stderr - testsuite/tests/parser/should_fail/readFail038.stderr - + testsuite/tests/parser/should_run/StringStartsWithNull.hs - + testsuite/tests/parser/should_run/StringStartsWithNull.stdout - testsuite/tests/parser/should_run/all.T - testsuite/tests/partial-sigs/should_compile/ExtraConstraints3.stderr - testsuite/tests/perf/compiler/T3064.hs - testsuite/tests/perf/compiler/hard_hole_fits.stderr - + testsuite/tests/pmcheck/should_compile/T27314.hs - + testsuite/tests/pmcheck/should_compile/T27360.hs - testsuite/tests/pmcheck/should_compile/all.T - testsuite/tests/polykinds/T7594.hs - testsuite/tests/printer/AnnotationNoListTuplePuns.stdout - testsuite/tests/printer/T18791.stderr - testsuite/tests/printer/Test20297.stdout - testsuite/tests/printer/Test24533.stdout - testsuite/tests/process/T3994.hs - testsuite/tests/programs/thurston-modular-arith/Main.hs - + testsuite/tests/rename/should_fail/T21101.hs - + testsuite/tests/rename/should_fail/T21101.stderr - testsuite/tests/rename/should_fail/T9815.stderr - testsuite/tests/rename/should_fail/T9815b.stderr - testsuite/tests/rename/should_fail/T9815bghci.stderr - testsuite/tests/rename/should_fail/T9815ghci.stderr - testsuite/tests/rename/should_fail/all.T - testsuite/tests/roles/should_compile/Roles14.stderr - testsuite/tests/roles/should_compile/Roles3.stderr - testsuite/tests/roles/should_compile/Roles4.stderr - testsuite/tests/roles/should_compile/T8958.stderr - + testsuite/tests/rts/T27123.hs - testsuite/tests/rts/all.T - testsuite/tests/rts/ipe/IpeStats/Fold.hs - testsuite/tests/runghc/T7859.stderr-mingw32 - testsuite/tests/simd/should_run/doublex2_arith.hs - testsuite/tests/simd/should_run/doublex2_arith.stdout - testsuite/tests/simd/should_run/doublex2_arith_baseline.hs - testsuite/tests/simd/should_run/doublex2_arith_baseline.stdout - testsuite/tests/simd/should_run/doublex2_fma.hs - testsuite/tests/simd/should_run/doublex2_fma.stdout - testsuite/tests/simd/should_run/simd010.hs - testsuite/tests/simplCore/should_compile/DataToTagFamilyScrut.stderr - testsuite/tests/simplCore/should_compile/T11562.hs - testsuite/tests/simplCore/should_compile/T14978.stdout - testsuite/tests/simplCore/should_compile/T18013.stderr - testsuite/tests/simplCore/should_compile/T24229a.stderr - testsuite/tests/simplCore/should_compile/T24229b.stderr - testsuite/tests/simplCore/should_run/T3591.hs - testsuite/tests/typecheck/should_compile/DeepSubsumption02.hs - testsuite/tests/typecheck/should_compile/T12507.hs - testsuite/tests/typecheck/should_compile/T13951.hs - testsuite/tests/typecheck/should_compile/T15242.stderr - testsuite/tests/typecheck/should_compile/T18406b.stderr - testsuite/tests/typecheck/should_compile/T18529.stderr - testsuite/tests/typecheck/should_compile/T18920.hs - testsuite/tests/typecheck/should_compile/T2595.hs - testsuite/tests/typecheck/should_compile/T7541.hs - + testsuite/tests/typecheck/should_compile/WarnDefaultedCallStack.hs - + testsuite/tests/typecheck/should_compile/WarnDefaultedCallStack.stderr - testsuite/tests/typecheck/should_compile/all.T - testsuite/tests/typecheck/should_fail/T15067.stderr - + testsuite/tests/typecheck/should_fail/T26532.hs - + testsuite/tests/typecheck/should_fail/T26532.stderr - testsuite/tests/typecheck/should_fail/T5300.stderr - testsuite/tests/typecheck/should_fail/T6069.stderr - testsuite/tests/typecheck/should_fail/T7368a.hs - testsuite/tests/typecheck/should_fail/T9858b.stderr - testsuite/tests/typecheck/should_fail/TcStaticPointersFail02.stderr - testsuite/tests/typecheck/should_fail/all.T - testsuite/tests/typecheck/should_run/T1735_Help/Basics.hs - testsuite/tests/typecheck/should_run/T3731-short.hs - testsuite/tests/typecheck/should_run/T3731.hs - testsuite/tests/typecheck/should_run/church.hs - testsuite/tests/typecheck/should_run/tcrun008.hs - testsuite/tests/typecheck/should_run/tcrun017.hs - testsuite/tests/typecheck/should_run/tcrun026.hs - testsuite/tests/typecheck/should_run/tcrun035.hs - testsuite/tests/typecheck/should_run/tcrun036.hs - utils/check-exact/ExactPrint.hs - utils/check-exact/Main.hs - utils/check-exact/Transform.hs - utils/check-exact/Utils.hs - utils/check-exact/check-exact.cabal - utils/deriveConstants/Main.hs - utils/haddock/haddock-api/haddock-api.cabal - utils/haddock/haddock-api/src/Haddock/Backends/Hoogle.hs - utils/haddock/haddock-api/src/Haddock/Backends/Hyperlinker/Parser.hs - utils/haddock/haddock-api/src/Haddock/Backends/LaTeX.hs - utils/haddock/haddock-api/src/Haddock/Backends/Xhtml/Decl.hs - utils/haddock/haddock-api/src/Haddock/Convert.hs - utils/haddock/haddock-api/src/Haddock/GhcUtils.hs - utils/haddock/haddock-api/src/Haddock/Interface/Create.hs - utils/haddock/haddock-api/src/Haddock/Interface/Rename.hs - utils/haddock/haddock-api/src/Haddock/Types.hs The diff was not included because it is too large. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/4933f5aa3b620931d4161a9540e32c… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/4933f5aa3b620931d4161a9540e32c… You're receiving this email because of your account on gitlab.haskell.org. Manage all notifications: https://gitlab.haskell.org/-/profile/notifications | Help: https://gitlab.haskell.org/help

1 0

[Git][ghc/ghc] Pushed new branch wip/devel2-again
by Zubin (＠wz1000) 27 Jul '26

27 Jul '26

Zubin pushed new branch wip/devel2-again at Glasgow Haskell Compiler / GHC -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/tree/wip/devel2-again You're receiving this email because of your account on gitlab.haskell.org. Manage all notifications: https://gitlab.haskell.org/-/profile/notifications | Help: https://gitlab.haskell.org/help

1 0

[Git][ghc/ghc] Pushed new tag ghc-9.12.5-rc3
by Magnus (＠MangoIV) 27 Jul '26

27 Jul '26

Magnus pushed new tag ghc-9.12.5-rc3 at Glasgow Haskell Compiler / GHC -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/tree/ghc-9.12.5-rc3 You're receiving this email because of your account on gitlab.haskell.org. Manage all notifications: https://gitlab.haskell.org/-/profile/notifications | Help: https://gitlab.haskell.org/help

1 0

[Git][ghc/ghc][wip/9.14.2-backports] Prepare 9.14.2
by Zubin (＠wz1000) 27 Jul '26

27 Jul '26

Zubin pushed to branch wip/9.14.2-backports at Glasgow Haskell Compiler / GHC Commits: 39eaaa65 by Zubin Duggal at 2026-07-27T15:33:11+05:30 Prepare 9.14.2 Bump filpath submodule to 1.5.5.0 Bump Win32 submodule to 2.14.2.2 Metric Increase: T4029 T13379 Metric Decrease: T5030 - - - - - 44 changed files: - − changelog.d/26616 - − changelog.d/T26978 - − changelog.d/T26979 - − changelog.d/T27046 - − changelog.d/T27047 - − changelog.d/T27123.md - − changelog.d/T27124.md - − changelog.d/T27131 - − changelog.d/T27182.md - − changelog.d/T27202 - − changelog.d/T27225 - − changelog.d/T27386 - − changelog.d/bump-process - − changelog.d/deterministic-usage-order - − changelog.d/fix-absent-dict-projection - − changelog.d/fix-blackhole-handling - − changelog.d/fix-cmm-atomic-load-store - − changelog.d/fix-compacting-gc-ap-27434 - − changelog.d/fix-exponential-case-desugar-27383 - − changelog.d/fix-finalizers-27072 - − changelog.d/fix-layout-stack-fcall - − changelog.d/fix-peekitbl-no-tntc - − changelog.d/fix-use-std-ap-thunk - − changelog.d/ghc-pkg-faster-closure - − changelog.d/hadrian-stale-package-confs-26661 - − changelog.d/jobserver-leak-fix - − changelog.d/more-efficient-home-unit-imports-finding - − changelog.d/reexported-module-errors - − changelog.d/semaphore-v2 - − changelog.d/tag-inference-27005 - − changelog.d/unused-type - − changelog.d/wasm-fix-serviceworker - − changelog.d/windows-rethrow-overlapped-exception - configure.ac - docs/users_guide/9.14.2-notes.rst - hadrian/bootstrap/generate_bootstrap_plans - + hadrian/bootstrap/plan-9_10_3.json - + hadrian/bootstrap/plan-9_12_4.json - + hadrian/bootstrap/plan-bootstrap-9_10_3.json - + hadrian/bootstrap/plan-bootstrap-9_12_4.json - libraries/Win32 - libraries/base/base.cabal.in - libraries/base/changelog.md - libraries/filepath The diff was not included because it is too large. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/39eaaa6599c174fdb21edd1f17ac6ae… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/39eaaa6599c174fdb21edd1f17ac6ae… You're receiving this email because of your account on gitlab.haskell.org. Manage all notifications: https://gitlab.haskell.org/-/profile/notifications | Help: https://gitlab.haskell.org/help

1 0

[Git][ghc/ghc][wip/9.14.2-backports] 26 commits: Reference correct package in error messages for reexported modules
by Zubin (＠wz1000) 27 Jul '26

27 Jul '26

Zubin pushed to branch wip/9.14.2-backports at Glasgow Haskell Compiler / GHC Commits: e757591a by Simon Hengel at 2026-07-27T15:14:26+05:30 Reference correct package in error messages for reexported modules (fixes #27417) (cherry picked from commit a805b2a25021606b30d250e084d4beecbfac0d0a) - - - - - fba13ef3 by Luite Stegeman at 2026-07-27T15:14:33+05:30 rts: handle large AP closures in compacting GC The function update_fwd_large in the compacting GC could run into an unexpected object with the following error: internal error: update_fwd_large: unknown/strange object 24 Closure type 24 is the AP closure, which was not handled in upd_fwd_large. This patch adds handling them. fixes #27434 (cherry picked from commit cca0d58963f802a8b2e43aa2dbc58592f8ad07bb) - - - - - 0500851f by Cheng Shao at 2026-07-27T15:14:33+05:30 compiler: fix missing handling of CmmUnsafeForeignCall node in LayoutStack This patch fixes missing handling of `CmmUnsafeForeignCall` middle node in the `LayoutStack` pass. Before proc-points splitting, this pass computes liveliness of local registers, and spills those alive across a Cmm native call onto the stack. It need to traverse all middle nodes in each block and check whether a local register is an assignee, if so then the previous mapping in `sm_regs` is invalidated and needs to be dropped. However, it didn't handle `CmmUnsafeForeignCall` node which may also assign to a local register. When proc-points splitting is enabled, this can produce an invalid basic block that doesn't properly backup the updated local register to the stack before doing a Cmm call, resulting in completely invalid runtime behavior. The patch also adds a `T27447` regression test. With no-TNTC or with LLVM backend, without the fix the test case would output a stale 0x1111111111111111 value, instead of the expected 0x2222222222222222 output. Fixes #27447. Co-authored-by: Codex <codex(a)openai.com> (cherry picked from commit 3f00f234d0d5b3b3b2a23a5dc70ce372eb9bbdb4) - - - - - 31af42e7 by Cheng Shao at 2026-07-27T15:14:33+05:30 ci: use treeless fetch for perf notes This patch improves the ci logic for fetching perf notes by using treeless fetch (https://github.blog/open-source/git/get-up-to-speed-with-partial-clone-and-…) to avoid downloading all blobs of the perf notes repo at once, and only fetch the actually required blobs on-demand when needed. This makes the initial `test-metrics.sh pull` operation much faster, and also more robust, since we are seeing an increasing rate of 504 errors in CI when fetching all perf notes at once, which is a major source of CI flakiness at this point. Co-authored-by: Codex <codex(a)openai.com> (cherry picked from commit 3c0013778b4459c1f8e56cd0dc2600f5bb3769d2) - - - - - a56fcdee by mangoiv at 2026-07-27T15:14:33+05:30 ci: retry fetching test metrics Retry fetching test metrics to make the CI not fail if the services is temporarily unavailable (cherry picked from commit b7e24044fde064cb3f0d44c36872a86d024cd7d4) - - - - - 03e870e1 by Zubin Duggal at 2026-07-27T15:14:33+05:30 Bump semaphore-compat submodule to 2.0.1 This versions includes some cruicial fixes for darwin (cherry picked from commit 4180af3f71754472dbd49b85179b25fd29bd9998) - - - - - 1eb8f64b by Zubin Duggal at 2026-07-27T15:14:33+05:30 CorePrep: Don't speculatively evaluate bindings that we have already discovered to be absent In #25924, we segfault because speculation forces a projection out of a RUBBISH dictionary (which we generated because it absent). Solution: Don't speculate on bindings we already know are absent. Fixes 25924 (cherry picked from commit 9b714c4c833461c621f0a050680848d7248aa57e) - - - - - 843e7885 by Zubin Duggal at 2026-07-27T15:14:33+05:30 Don't make absent fillers for terminating types In #25924 we discovered that we could speculatively evaluate an absent filler for a dictionary, and project a field (a superclass selector) out of it, resulting in segfaults. Solution: Never make an absent filler or rubbish literal for a terminating type like a dictionary. mkAbsentFiller returns Nothing for isTerminatingType, so worker/wrapper and the specialiser keep the real argument instead. Some small metric decreases because we do a little less work in the simplifier now. Metric Decrease: T9872a T9872b T9872c TcPlugin_RewritePerf (cherry picked from commit 4a59b3eece9b7106fcbe73d2d06a49755be4ea8f) - - - - - e8f1b190 by Andreas Klebinger at 2026-07-27T15:14:33+05:30 Fix a profiling race condition resulting in segfaults. StgToCmm: Don't assume tagged FUN closures in closureCodeBody. When entering a closure the self/node pointer might not be tagged in some situations when a thunk is evaluated by multiple threads. So we most AND away the tag bits rather than subtracting an expected tag. Apply.cmm: Fix a race condition occuring when a thunk is mutated during GC. In stg_ap_0_fast when might need to run GC before entering a thunk. If this happens another thread or the GC itself might mutate the closure making entering it no longer valid. We now check for this. Add test and changelog for #27123 fixes. (cherry picked from commit ed09895d7de1ca116a561868c151fd825a16ad0c) - - - - - f1cfd0f4 by Cheng Shao at 2026-07-27T15:14:33+05:30 ghc-heap: fix invalid srtlen returned by peekItbl when no-TNTC This patch fixes the no-TNTC code path of `peekItbl` so that it looks at the right memory address when reading the `srt` field from the `StgInfoTable_` struct. Also adds a `T27465` regression test that reproduces the bug on no-TNTC builds before the fix. Fixes #27465. Co-authored-by: Codex <codex(a)openai.com> (cherry picked from commit 67c03eb2c762fdfeb646eb8345341173dd4268b2) - - - - - ed840c99 by Cheng Shao at 2026-07-27T15:14:33+05:30 compiler: fix miscompiled %load_relaxed, add missing %store_relaxed This patch fixes the %load_relaxed cmm primop compilation logic to correctly use relaxed memory ordering, and adds the missing %store_relaxed primop. Parsing logic of %load/%store with explicit ordering is covered in the AtomicFetch test case. Fixes #27483. Co-authored-by: Codex <codex(a)openai.com> (cherry picked from commit eee8ec5b25ef0f83ba4822e7a0a941df7b0bec5f) - - - - - fc129385 by Cheng Shao at 2026-07-27T15:14:33+05:30 rts: fix missing UNTAG in stg_readTVarIOzh This patch fixes missing UNTAG on the current value closure read from StgTVar. UNTAG is a no-op when it's stg_TREC_HEADER_info which is word aligned; it may be a tagged closure, and reading info table from the tagged address is an unaligned load which may cause issues on platforms with strict alignment requirements. Co-authored-by: Codex <codex(a)openai.com> (cherry picked from commit d377e83e51d39a06e1f0bf2e35a923a3210b21a2) - - - - - 2e023223 by Cheng Shao at 2026-07-27T15:14:33+05:30 rts: fix missing UNTAG in stg_control0zh_ll This patch fixes missing UNTAG on the cont closure returned by captureContinuationAndAbort. In case it's not NULL, captureContinuationAndAbort returns a tagged StgContinuation closure, in which case it must be untagged before accessing the apply_mask_frame field. In the past it worked out of luck: when apply_mask_frame was NULL then mask_frame_offset is also 0 so the control flow didn't diverge to a wrong path. Still, this is horribly wrong and will crash once StgContinuation struct is refactored and fields are shuffled around. Co-authored-by: Codex <codex(a)openai.com> (cherry picked from commit 8ed038421a20e3e4e681973b2f5098e5bd2144b5) - - - - - a52c471f by Cheng Shao at 2026-07-27T15:14:33+05:30 compiler: fix redundant AP thunk codegen when not using -ticky-ap-thunk This patch fixes a double negation confusion in !7525 that results in some redundant AP thunk code generation when not using -ticky-ap-thunk. Now, we use `stgToCmmUseStdApThunk` to indicate whether precomputed AP thunks in the RTS should be used, which defaults to `True`, unless `-ticky-ap-thunk` is passed. `-finfo-table-map` now also implies `-ticky-ap-thunk`, since when doing IPE profiling we want the generated AP thunks to be unique. Fixes #27502. ------------------------- Metric Decrease: T3064 ------------------------- Co-authored-by: Codex <codex(a)openai.com> (cherry picked from commit 5aa7000ae246ae6a706437799338295b5801a629) - - - - - d26793ae by sheaf at 2026-07-27T15:14:33+05:30 Avoid mkTick in Core Prep breaking ANF As discovered in #27182, mkTick can break ANF. This patch introduces a variant of mkTick that skips the single optimisation that could break ANF. This is preferrable over switching to the raw Tick constructor, as the latter may introduce spurious cost centres in profiling reports. This is a temporary measure until we more thoroughly refactor how mkTick works (see #27141). See Note [mkTick breaks ANF] in GHC.CoreToStg.Prep. Fixes #27182 (cherry picked from commit f9bcfac2e92457128f5c82dea181edcd0baf7eef) - - - - - 34061ece by sheaf at 2026-07-27T15:14:33+05:30 Don't drop ticks around variables of type `IO ()` GHC.Core.Utils.mkTick is responsible for placing a tick on a Core expression. It contains logic for dropping SCCs (non-counting profiling ticks) around non-function variables, as such variables cannot meaningfully contribute to profiles. However, the logic for what counts as a function was incorrect: it used `isFunTy` which returns 'False' for types such as 'IO ()' where the function arrow is hidden under a newtype. We now use 'mightBeFunTy' instead of 'isFunTy'. This ensures we don't drop ticks in cases we aren't sure. On the way, we improve the documentation of 'isFunTy', 'isPiTy' and 'mightBeFunTy', and update the latter's implementation to consistently handle unary classes. Fixes #27225 ------------------------- Metric Decrease: T5642 ------------------------- (cherry picked from commit ce01ccb625514a09e76aded549691da4dfe87de7) - - - - - e908040d by sheaf at 2026-07-27T15:14:33+05:30 Avoid mkTick in Core Prep breaking ANF (part II) Hotfix for 2f9579765f55b3920ceb2e04995ff41a9d0e2d4e fixing a small oversight in the call to tickTickedExpr from mkTick, in which we improperly recursively called mkTick without passing on the preserve_anf flag. Fixes #27386 (cherry picked from commit 473b97ebc742305f56e30d5b1bbf95b7681312f0) - - - - - 6bdf75ab by Ian-Woo Kim at 2026-07-27T15:14:33+05:30 Make the order of usages deterministic It has been observed that the ordering of usages can be non-determinstic in parallel builds. Therefore, this contribution introduces sorting of usages based on a platform- and race-independent sorting criterion. Resolves #26877. Co-authored-by: Wolfgang Jeltsch <wolfgang(a)well-typed.com> (cherry picked from commit d216412babfd5b5746365f0686ec370fb0892ec7) - - - - - 6382e45c by Wolfgang Jeltsch at 2026-07-27T15:14:33+05:30 Change the descriptions of two existing changelog entries The descriptions now describe the changes in a user-friendly manner, as opposed to describing the contributions that led to these changes in a developer-friendly manner. (cherry picked from commit 8e1cc105acae69b1fabd1a9b89e2d1823861f518) - - - - - a8cb9679 by Andrea Vezzosi at 2026-07-27T15:14:33+05:30 [Fix #27287] preserve ModBreaks in ModIface (cherry picked from commit 4396a6f2a4c7799908e1e0b88a218a51d063fdca) - - - - - 14691377 by mangoiv at 2026-07-27T15:14:33+05:30 compiler: refactor error reporting code for ExplicitLevelImports Refactors error reporting code for ExplicitLevelImports to pass in a RdrName and a GlobalReaderElt to be able to report errors that are faithful to the source and to more precisely distinguish between names that are in scope from different qualifications. Fixes #27385 and #26616 (cherry picked from commit 141986e3680a24b76e21a7ad4ce6290a7413c7f5) - - - - - d3099986 by mangoiv at 2026-07-27T15:14:33+05:30 compiler: rename ZonkAny to UnusedType and add pretty printing logic ZonkAny is a hard to understand name for users who do not know how the compiler works internally. Additionally, it is confusing that ZonkAny, while being a concrete type *represents* a meta variable, espeically in the compiler output. This patch changes the name of ZonkAny to UnusedType which is closer to its intended semantics and adds special pretty printing logic to display this type in the same fashion the compiler displays meta variables in other places, whenever they leak from the implementation to the user. It also exports the type from ghc-internal:GHC.Internal.Types in order to expose documentation. Fixes #27390 Co-Authored-By: Sam Derbyshire <sam.derbyshire(a)gmail.com> (cherry picked from commit a72ff58fa86172b1557e405f7246d27914fdae6e) - - - - - 8ad5f8f7 by Zubin Duggal at 2026-07-27T15:14:33+05:30 hadrian: Remove old package.conf files when generating new ones Old package.conf files might exists with different hashes, causing issues like #26661 Fixes #26661 (cherry picked from commit 5ac9ce7d3821c75e2d2cc17fae00b9e865a02987) - - - - - 1b612594 by Zubin Duggal at 2026-07-27T15:14:33+05:30 testsuite: disable git auto-gc when fetching perf notes Otherwise the message it prints breaks the parsing - - - - - d1651dfd by Zubin Duggal at 2026-07-27T15:14:54+05:30 UniqueDFM: alter should preserve insertion order Before it always inserting new elements at the end. This is problematic because instances get inserted into the map with `alterF`, which can change ordering of how instances are printed with `:info` depending on the order in which we consult interfaces I expect `alter id k = id` and `alter (fmap f) k = adjust f k`. Moving keys to the end breaks that (`adjust` already preserves position). Fixes #27532 (cherry picked from commit f6f2343fbbfdfd8aaed9babf5983e3e24c08ca85) - - - - - 391df98b by Zubin Duggal at 2026-07-27T15:14:54+05:30 Prepare 9.14.2 Bump filpath submodule to 1.5.5.0 Bump Win32 submodule to 2.14.2.2 Metric Increase: T4029 T13379 Metric Decrease: T5030 - - - - - 230 changed files: - .gitlab/test-metrics.sh - − changelog.d/T26978 - − changelog.d/T26979 - − changelog.d/T27046 - − changelog.d/T27047 - − changelog.d/T27124.md - − changelog.d/T27131 - − changelog.d/T27202 - − changelog.d/bump-process - − changelog.d/fix-blackhole-handling - − changelog.d/fix-exponential-case-desugar-27383 - − changelog.d/fix-finalizers-27072 - − changelog.d/ghc-pkg-faster-closure - − changelog.d/jobserver-leak-fix - − changelog.d/more-efficient-home-unit-imports-finding - − changelog.d/semaphore-v2 - − changelog.d/tag-inference-27005 - − changelog.d/wasm-fix-serviceworker - − changelog.d/windows-rethrow-overlapped-exception - compiler/GHC/Builtin/Names.hs - compiler/GHC/Builtin/Types.hs - compiler/GHC/ByteCode/Breakpoints.hs - compiler/GHC/ByteCode/Types.hs - compiler/GHC/Cmm/LayoutStack.hs - compiler/GHC/Cmm/Parser.y - compiler/GHC/Core/Make.hs - compiler/GHC/Core/Opt/Arity.hs - compiler/GHC/Core/Opt/Specialise.hs - compiler/GHC/Core/Opt/WorkWrap.hs - compiler/GHC/Core/Opt/WorkWrap/Utils.hs - compiler/GHC/Core/Type.hs - compiler/GHC/Core/Utils.hs - compiler/GHC/CoreToStg/Prep.hs - compiler/GHC/Driver/Config/StgToCmm.hs - compiler/GHC/Driver/Flags.hs - compiler/GHC/Driver/Main.hs - compiler/GHC/Hs/Expr.hs - compiler/GHC/HsToCore/Breakpoints.hs - + compiler/GHC/HsToCore/Breakpoints/Types.hs - compiler/GHC/HsToCore/Expr.hs - compiler/GHC/HsToCore/Usage.hs - compiler/GHC/Iface/Errors.hs - compiler/GHC/Iface/Errors/Ppr.hs - compiler/GHC/Iface/Errors/Types.hs - compiler/GHC/Iface/Load.hs - compiler/GHC/Iface/Make.hs - compiler/GHC/Iface/Recomp.hs - compiler/GHC/Iface/Type.hs - compiler/GHC/Linker/Types.hs - compiler/GHC/Rename/Env.hs - compiler/GHC/Rename/Expr.hs - compiler/GHC/Rename/HsType.hs - compiler/GHC/Rename/Module.hs - compiler/GHC/Rename/Pat.hs - compiler/GHC/Rename/Splice.hs - compiler/GHC/Rename/Splice.hs-boot - compiler/GHC/Rename/Unbound.hs - compiler/GHC/Runtime/Interpreter.hs - compiler/GHC/StgToCmm/Bind.hs - compiler/GHC/StgToCmm/Config.hs - compiler/GHC/Tc/Errors.hs - compiler/GHC/Tc/Errors/Ppr.hs - compiler/GHC/Tc/Errors/Types.hs - compiler/GHC/Tc/Gen/Export.hs - compiler/GHC/Tc/Types.hs - compiler/GHC/Tc/Utils/Env.hs - compiler/GHC/Tc/Utils/Monad.hs - compiler/GHC/Tc/Utils/TcType.hs - compiler/GHC/Tc/Zonk/Type.hs - compiler/GHC/Types/Literal.hs - compiler/GHC/Types/Name/Reader.hs - compiler/GHC/Types/RepType.hs - compiler/GHC/Types/Unique/DFM.hs - compiler/GHC/Unit/Finder.hs - compiler/GHC/Unit/Finder/Types.hs - compiler/GHC/Unit/Module/Deps.hs - compiler/GHC/Unit/Module/ModGuts.hs - compiler/GHC/Unit/Module/ModIface.hs - compiler/GHC/Unit/Module/WholeCoreBindings.hs - compiler/GHC/Unit/State.hs - compiler/GHC/Utils/Binary.hs - compiler/ghc.cabal.in - configure.ac - docs/users_guide/9.14.2-notes.rst - ghc/GHCi/UI/Exception.hs - hadrian/src/Hadrian/Haskell/Cabal/Parse.hs - hadrian/src/Settings/Warnings.hs - libraries/Win32 - libraries/base/base.cabal.in - libraries/base/changelog.md - libraries/base/src/GHC/Base.hs - libraries/base/src/GHC/Exts.hs - libraries/filepath - libraries/ghc-experimental/src/GHC/PrimOps.hs - + libraries/ghc-heap/tests/T27465.hs - + libraries/ghc-heap/tests/T27465.stdout - libraries/ghc-heap/tests/all.T - libraries/ghc-internal/src/GHC/Internal/Heap/InfoTable.hsc - libraries/ghc-internal/src/GHC/Internal/Heap/InfoTableProf.hsc - libraries/ghc-internal/src/GHC/Internal/Types.hs - libraries/semaphore-compat - rts/Apply.cmm - rts/ContinuationOps.cmm - rts/PrimOps.cmm - rts/sm/Compact.c - testsuite/driver/perf_notes.py - testsuite/tests/annotations/should_fail/annfail03.stderr - testsuite/tests/annotations/should_fail/annfail04.stderr - testsuite/tests/annotations/should_fail/annfail06.stderr - testsuite/tests/annotations/should_fail/annfail09.stderr - testsuite/tests/cmm/should_run/AtomicFetch.hs - testsuite/tests/cmm/should_run/AtomicFetch_cmm.cmm - + testsuite/tests/cmm/should_run/T27447.hs - + testsuite/tests/cmm/should_run/T27447.stdout - + testsuite/tests/cmm/should_run/T27447_cmm.cmm - testsuite/tests/cmm/should_run/all.T - + testsuite/tests/core-to-stg/T25924/B.hs - + testsuite/tests/core-to-stg/T25924/Main.hs - + testsuite/tests/core-to-stg/T25924/all.T - + testsuite/tests/core-to-stg/T25924a.hs - + testsuite/tests/core-to-stg/T25924a.stdout - testsuite/tests/core-to-stg/all.T - testsuite/tests/count-deps/CountDepsAst.stdout - testsuite/tests/count-deps/CountDepsParser.stdout - testsuite/tests/dmdanal/should_compile/T18982.stderr - testsuite/tests/ghci/T16793/T16793.stdout - testsuite/tests/ghci/T18060/T18060.stdout - + testsuite/tests/ghci/T27532/Makefile - + testsuite/tests/ghci/T27532/T27532.stdout - + testsuite/tests/ghci/T27532/T27532j4.stdout - + testsuite/tests/ghci/T27532/a.script - + testsuite/tests/ghci/T27532/all.T - + testsuite/tests/ghci/T27532/b.script - + testsuite/tests/ghci/T27532/genT27532Modules - testsuite/tests/ghci/scripts/ListTuplePunsPpr.stdout - testsuite/tests/ghci/scripts/T4175.stdout - testsuite/tests/ghci/scripts/T8469.stdout - testsuite/tests/ghci/scripts/T8535.stdout - testsuite/tests/ghci/scripts/T9881.stdout - testsuite/tests/ghci/scripts/ghci020.stdout - testsuite/tests/ghci/scripts/ghci064.stdout - testsuite/tests/ghci/should_run/Makefile - testsuite/tests/ghci/should_run/T10145.stdout - testsuite/tests/ghci/should_run/T18594.stdout - + testsuite/tests/ghci/should_run/T27287.hs - + testsuite/tests/ghci/should_run/T27287.stdout - testsuite/tests/ghci/should_run/all.T - testsuite/tests/interface-stability/ghc-prim-exports.stdout - testsuite/tests/interface-stability/ghc-prim-exports.stdout-mingw32 - testsuite/tests/linters/notes.stdout - + testsuite/tests/package/ImportReexport.hs - + testsuite/tests/package/ImportReexport.stderr - testsuite/tests/package/all.T - testsuite/tests/partial-sigs/should_compile/ExtraConstraints3.stderr - testsuite/tests/perf/compiler/T11068.stdout - testsuite/tests/pmcheck/should_compile/T12957.stderr - + testsuite/tests/profiling/should_compile/T27182.hs - + testsuite/tests/profiling/should_compile/T27386.hs - testsuite/tests/profiling/should_compile/all.T - + testsuite/tests/profiling/should_run/T27225.hs - + testsuite/tests/profiling/should_run/T27225.stdout - + testsuite/tests/profiling/should_run/T27225b.hs - + testsuite/tests/profiling/should_run/T27225b.stdout - testsuite/tests/profiling/should_run/all.T - testsuite/tests/profiling/should_run/caller-cc/CallerCc1.prof.sample - testsuite/tests/profiling/should_run/callstack001.stdout - testsuite/tests/profiling/should_run/scc001.prof.sample - testsuite/tests/profiling/should_run/staticcallstack002.stdout - testsuite/tests/quasiquotation/qq001/qq001.stderr - testsuite/tests/quasiquotation/qq002/qq002.stderr - testsuite/tests/quasiquotation/qq003/qq003.stderr - testsuite/tests/quasiquotation/qq004/qq004.stderr - testsuite/tests/quotes/LiftErrMsg.stderr - testsuite/tests/quotes/LiftErrMsgDefer.stderr - testsuite/tests/quotes/LiftErrMsgTyped.stderr - testsuite/tests/quotes/T10384.stderr - testsuite/tests/quotes/T5721.stderr - testsuite/tests/quotes/TH_localname.stderr - testsuite/tests/roles/should_compile/Roles14.stderr - testsuite/tests/roles/should_compile/Roles3.stderr - testsuite/tests/roles/should_compile/Roles4.stderr - testsuite/tests/roles/should_compile/T8958.stderr - + testsuite/tests/rts/T27123.hs - + testsuite/tests/rts/T27434.hs - + testsuite/tests/rts/T27434.stdout - testsuite/tests/rts/all.T - testsuite/tests/simplCore/should_compile/Makefile - testsuite/tests/simplCore/should_compile/T13156.stdout - testsuite/tests/splice-imports/SI03.stderr - testsuite/tests/splice-imports/SI05.stderr - testsuite/tests/splice-imports/SI08.stderr - testsuite/tests/splice-imports/SI08_oneshot.stderr - testsuite/tests/splice-imports/SI16.stderr - testsuite/tests/splice-imports/SI18.stderr - testsuite/tests/splice-imports/SI20.stderr - testsuite/tests/splice-imports/SI25.stderr - testsuite/tests/splice-imports/SI28.stderr - testsuite/tests/splice-imports/SI29.stderr - testsuite/tests/splice-imports/SI31.stderr - testsuite/tests/splice-imports/SI36.stderr - testsuite/tests/splice-imports/T26088.stderr - testsuite/tests/splice-imports/T26090.stderr - + testsuite/tests/splice-imports/T26616.hs - + testsuite/tests/splice-imports/T26616.stderr - testsuite/tests/splice-imports/all.T - testsuite/tests/th/T16976z.stderr - testsuite/tests/th/T17820a.stderr - testsuite/tests/th/T17820b.stderr - testsuite/tests/th/T17820c.stderr - testsuite/tests/th/T17820d.stderr - testsuite/tests/th/T17820e.stderr - testsuite/tests/th/T21547.stderr - testsuite/tests/th/T23829_hasty.stderr - testsuite/tests/th/T23829_hasty_b.stderr - testsuite/tests/th/T23829_tardy.ghc.stderr - testsuite/tests/th/T26098_local.stderr - testsuite/tests/th/T26098_quote.stderr - testsuite/tests/th/T26098_splice.stderr - testsuite/tests/th/T26099.stderr - testsuite/tests/th/T26568.stderr - testsuite/tests/th/T5795.stderr - testsuite/tests/typecheck/should_compile/T18406b.stderr - testsuite/tests/typecheck/should_compile/T18529.stderr - testsuite/tests/typecheck/should_fail/T13292.stderr - + testsuite/tests/typecheck/should_fail/T27390-explicit-kinds.stderr - + testsuite/tests/typecheck/should_fail/T27390.hs - + testsuite/tests/typecheck/should_fail/T27390.stderr - + testsuite/tests/typecheck/should_fail/T27390a.hs - testsuite/tests/typecheck/should_fail/T5300.stderr - testsuite/tests/typecheck/should_fail/all.T The diff was not included because it is too large. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/d0cd71ee05a722f3302de66fefbb8a… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/d0cd71ee05a722f3302de66fefbb8a… You're receiving this email because of your account on gitlab.haskell.org. Manage all notifications: https://gitlab.haskell.org/-/profile/notifications | Help: https://gitlab.haskell.org/help

1 0

[Git][ghc/ghc][wip/romes/27461] 35 commits: Eliminate STM_AWOKEN
by Hannes Siebenhandl (＠fendor) 27 Jul '26

27 Jul '26

Hannes Siebenhandl pushed to branch wip/romes/27461 at Glasgow Haskell Compiler / GHC Commits: 4d798b17 by Duncan Coutts at 2026-07-23T17:26:18-04:00 Eliminate STM_AWOKEN It was used as nullary closure for the block_info.closure in the case of a thread being awoken after an STM transaction. However, while it was written, it was never read, so contributed nothing to the behaviour. Furthermore, in the only place it was set (in tryWakeupThread) the why_blocked was immediately overwritten by the NotBlocked status, and the block_info was updated accordingly (by appendToRunQueue). So it didn't even serve a purpose of clarifying an intermediate state, there really was no such intermediate state. Cleaning this up will allow the BlockedOnSTM case to follow the same pattern as the other why_blocked cases that do not use the block_info, and in turn this reduces the number of different categories. - - - - - e1cece79 by Duncan Coutts at 2026-07-23T17:26:18-04:00 Document that eventlog thread stop code ThreadBlocked is no longer used It has not been used since GHC 7.0.x (2011). In 7.2 all the BlockedOn* codes were added, and these were and are used instead of ThreadBlocked. - - - - - 795db115 by Duncan Coutts at 2026-07-23T17:26:18-04:00 Add a proper mapping to eventlog external thread stop status That is the mapping from rts-internal codes, to the coes used in the status field in the eventlog EVENT_STOP_THREAD event. See issue #9003 for what goes wrong when we mess this up. In that ticket, people note that we should really not require the internal tso->why_blocked codes to leak into the external eventlog thread stop codes. The same principle applies to the StgThreadReturnCode. This change properly separates them, and explicitly maps between them using a pair of (compact, constant) tables. These tables are pretty small (with no alignment constraints) and will soon shrink so it seems a sensible tradeoff. We also introduce and use proper EVENT_STOP_THREAD constants in the event log format header. Previously there was not specification in the code for these (only in the docs): the values were encoded into the conversion code. This will allow us to renumber the internal why_blockd codes without breaking the eventlog output. - - - - - 6f1c8efa by Duncan Coutts at 2026-07-23T17:26:18-04:00 Remove unused tso->block_info.wakeup member Presumably it was used once, but not now. - - - - - 740b88a9 by Duncan Coutts at 2026-07-23T17:26:18-04:00 Document StgTSOBlockInfo to say what cases use what members In principle, tso->why_blocked is the tag for the StgTSOBlockInfo union, so we should be able to say for each union member the why_blocked cases that use that member. - - - - - 5b92eae2 by Duncan Coutts at 2026-07-23T17:26:18-04:00 Add a tso->block_info.mvar member and use it in preference to the generic block_info.closure union member, with casts. The plan is that when we know what case we're in (via tso->why_blocked) then we can always access the correct union member, and so we will only need to access block_info.closure for generic cases where we don't know or don't care. - - - - - d931715f by Duncan Coutts at 2026-07-23T17:26:18-04:00 Add a tso->block_info.unused member and use it in preference to the generic block_info.closure union member, with casts. The plan is that when we know what case we're in (via tso->why_blocked) then we can always access the correct union member, and so we will only need to access block_info.closure for generic cases where we don't know or don't care. - - - - - 47e28ebb by Duncan Coutts at 2026-07-23T17:26:18-04:00 Avoid storing to tso->block_info.closure In one case we can use a specific union member (.prev) instead. In several cases the stores were in fact redundant because of subsequent overwrites. In scavengeTSO we replace setting tso->block_info.closure to a valid closure, with an assertion that the block_info.unused is already set to END_TSO_QUEUE which is a valid (static) closure. - - - - - 96e4749d by Duncan Coutts at 2026-07-23T17:26:18-04:00 Renumber the tso->why_blocked constants We can do this now because we have separated the internal values from the external ones used in the eventlog. This lets us put them back into a deliberate order and consolodate some gaps. More importantly, it is a prepation for a slightly more sophisticated encoding. - - - - - 8f62661c by Duncan Coutts at 2026-07-23T17:26:18-04:00 Define constants for the existing stg_threadStatuszh return codes The stg_threadStatuszh reuses the internal tso->why_blocked codes but also extends them with a couple previously magic values. This is awkward since we need to know what those magic values are so we don't accidentally use those values to mean something else. By pulling a definition up to where the why_blocked codes are defined we will be able to avoid mistakenly assining those codes some meaning (or just changing the BlockedThreadComplete, BlockedThreadKilled code if necessary). - - - - - 42c69ae2 by Duncan Coutts at 2026-07-23T17:26:18-04:00 Extend the tso->why_blocked encoding to indicate block_info closures We use some bit tricks to cheaply and generically test if a tso->why_blocked tag implies that the corresponding tso->block_info will contain a non-trivial valid closure (i.e. not just block_info.unused set to END_TSO_QUEUE). In particular we arrange for most why_blocked values to naturally have a distinguishing bit, but for the BlockedOn{Read,Write,Delay} cases, they can come in either non-closure or closure forms. We allow an additional bit to distinguish these cases. The non-closure forms are only from legacy I/O managers: select and win32-legacy. So this extra bit mechanism will be able to be retired once the legacy I/O managers are themselves retired. This means in a few places we need to untag the why_blocked value before inspecting it, but in most places we do not. - - - - - 7c64632b by Duncan Coutts at 2026-07-23T17:26:18-04:00 Use BlockInfoForceNonClosure in the select I/O manager - - - - - 8fd7104a by Duncan Coutts at 2026-07-23T17:26:18-04:00 Use BlockInfoForceNonClosure in the win32-legacy I/O manager for the BlockedOn{Read,Write} since these use the non-heap allocated StgAsyncIOResult. - - - - - e0da603b by Duncan Coutts at 2026-07-23T17:26:18-04:00 Enforce the why_blocked and block_info rules in checkTSO We now check the cases wher IsBlockInfoClosure should hold, the cases that are supposed to use block_info.unused == END_TSO_QUEUE, and which cases are allowed to use BlockInfoForceNonClosure. This partially enforces the use of why_blocked as a tag for the block_info union. We could be stricter and check for the correct expected info table for the closure cases. - - - - - 1dd0f381 by Duncan Coutts at 2026-07-23T17:26:18-04:00 Use IsBlockInfoClosure to simplify several tests In GC and generic traversal we need to know if we should look at the block_info.closure or not. Now we can do just that using a cheap bit test on the why_blocked tag. This fixes issue 26717, where the problem was that some GC modes did not know when to look at block_info.closure, because the poll I/O manager uses a closure for BlockedOn{Read,Write} while the select I/O manager uses a non-closure. Now this information is in the why_blocked tag itself. - - - - - 7a00ffbc by Duncan Coutts at 2026-07-23T17:26:18-04:00 Remove the now-unused scavengeTSOIOManager The GC no longer has to delegate to the I/O manager, since it can use IsBlockInfoClosure to decide things itself. - - - - - 522a481f by Duncan Coutts at 2026-07-23T17:26:18-04:00 Remove duplicate assertion - - - - - 0874d965 by Duncan Coutts at 2026-07-23T17:26:18-04:00 Follow atomic access rules more consistently for tso->why_blocked The rule is this: store block_info *before* why_blocked store why_blocked using store release load why_blocked using load acquire load block_info *after* why_blocked This is a an atomic store release / load acquire pair and (if the reads are in a separate thread to the writes, and the read receives the value stored) then this guarantees a full "happens before" relationship of these stores and loads. In some cases, we do not need a full load acquire, because we don't read the block_info at all and so do not need any ordering. In this case we just need an atomic relaxed load. This was being followed in most places, but not all. If there's good reason in any case that we don't need atomic access, then we should document that in a comment. In the absence of that I think it's easier to follow the rule everywhere. - - - - - 8f0bdbe1 by Duncan Coutts at 2026-07-23T17:26:19-04:00 Add a changelog entry - - - - - 4fdfe757 by Alan Zimmerman at 2026-07-23T17:27:06-04:00 EPA: Keep decls together in ClassDecl Similar to 1718230f4d3d19d8c49c0e5d496cb0fb6f399528 for HsValBindsLR, this commit updates ClassDecl so that it no longer splits out the assorted `LHsDecl GhcPs` until the renamer. It does this by inserting a type family (separate from the classic TTG one) for this. So data TyClDecl ... | ClassDecl { ... tcdDecls :: XClassDecls pass with type instance XClassDecls GhcPs = [LHsDecl GhcPs] type instance XClassDecls GhcRn = ClassDeclX GhcRn type instance XClassDecls GhcTc = ClassDeclX GhcTc data ClassDeclX pass = ClassDeclX { tcdSigs :: [LSig pass], -- ^ Methods' signatures tcdMeths :: LHsBinds pass, -- ^ Default methods tcdATs :: [LFamilyDecl pass], -- ^ Associated types; tcdATDefs :: [LTyFamDefltDecl pass], -- ^ Associated type defaults tcdDocs :: [LDocDecl pass] -- ^ Haddock docs } - - - - - f586c885 by Simon Jakobi at 2026-07-24T18:05:00-04:00 ci: Use shallow submodule clones by default Limit submodule clones to depth one to reduce CI checkout costs. Keep fetching full submodule history for the submodule lint jobs, which inspect commits across a range. Assisted-by: gpt-5.6-sol via Codex CLI - - - - - 306120d2 by Duncan Coutts at 2026-07-24T18:05:43-04:00 Fix flaky test T3994 on FreeBSD On current FreeBSD versions, calling getpgid on a zombie process fails. In T3994, if we're really unlucky with delays and scheduling then we can end up in exactly that situation. Just catch that specific exception and ignore it. It's rare, and not our fault. - - - - - 7b116a0b by Cheng Shao at 2026-07-24T18:06:24-04:00 ci: add missing workaround for docker permissions in lint jobs Some lint jobs use ci-images with default user `ghc`, and the gitlab ci docker executor requires the `sudo chown` workaround to fix workspace directory permission issue. This patch adds the missing workarounds for the lint jobs. Fixes #27554. Co-authored-by: Codex <codex(a)openai.com> - - - - - 815149f3 by Andrzej Rybczak at 2026-07-25T15:06:43+00:00 Add -Wdefaulted-callstack Adds a new warning, -Wdefaulted-callstack, which warns when an implicit CallStack parameter is defaulted to the empty stack. In particular, this includes call sites where a function with a HasCallStack constraint is called from a definition that does *not* provide one. At such call sites the call stack is cut off and does not include the enclosing definition's callers, which can be a source of surprise if the user wants complete call stacks. Closes #27077. - - - - - f6f2343f by Zubin Duggal at 2026-07-25T17:40:51-04:00 UniqueDFM: alter should preserve insertion order Before it always inserting new elements at the end. This is problematic because instances get inserted into the map with `alterF`, which can change ordering of how instances are printed with `:info` depending on the order in which we consult interfaces I expect `alter id k = id` and `alter (fmap f) k = adjust f k`. Moving keys to the end breaks that (`adjust` already preserves position). Fixes #27532 - - - - - 293da2e1 by Rodrigo Mesquita at 2026-07-27T10:51:23+02:00 loopImports: Don't dup ms_uid in summary imports We were writing the ms_unitid of the mod summary with every single import of that module That complicated the code (as though the UnitId in that list could ever be something else) and also allocates unnecessarily per every mod import. Very slight allocation decrease measured locally in a few tests: (MultiComponentModulesRecomp: -0.06%; MultiComponentModulesRecomp100: -0.05%) Purely a clean up. - - - - - 74dc56a1 by Rodrigo Mesquita at 2026-07-27T10:51:23+02:00 downsweep: make control flow simpler and cache correct This refactor extracts the control flow of downsweep into a single function `dfsBuild`, which takes care of iteratively expanding and traversing all nodes of the in-construction module graph necessary to build a full `ModuleGraph`. There are three levels of caching going on, all of which are necessary to make sure we don't do repeated work (notably, NEVER summarise the same module twice). 1. `dfsBuild` accumulates the final module graph and never revisits the same node of the module graph. Cache is keyed by the final `ModuleGraph`s `NodeKey`s. 2. For Module A in home-unit u1, each import in the list of imports needs to be *found* (call to `findImportedModuleWithIsBoot`): at this point, we only have the `ModuleName` of the import, not the `Module`. This *finding* is somewhat expensive, so we cache it as well (`ImportsCache`). The cache key is the home-unit to which the module belongs~[1], the import package qualifier, and the ModuleName. [1] Different home-units will have different package flags, which means potentially different `Module` resolution for the same `ModuleName`. 3. The most expensive operation we want to avoid is summarising a `Module` into a `ModSummary`, which notably involves parsing the module header from scratch. The third cache, in essence, maps a `Module` to its `ModSummary` (named `ModSummaryCache`). This cache upholds the invariant: we NEVER summarise the same module twice. In practice, the cache key is the Module's UnitId and the Source path; the reason is we need to distinguish between `.hs` and `.hs-boot` files, as their summaries will differ. Note that (2) can't guarantee this alone: Two ModuleName imports in separate units can (and likely do) map to the same `Module`. Note that the previous implementation failed to achieve the no-duplicate-work summarisation invariant, and we ended up doing a quadratic amount of processing in scenarios like test `MultiComponentModules100`. See also Note [Downsweep Control Flow and Caching] Fixes #27461 Perf changes: MultiComponentModules(normal) ghc/alloc 2,097,389,264 1,992,186,736 -5.0% GOOD MultiComponentModules100(normal) ghc/alloc 24,310,173,770 21,293,867,360 -12.4% GOOD MultiComponentModulesRecomp(normal) ghc/alloc 602,761,394 498,543,984 -17.3% GOOD MultiComponentModulesRecomp100(normal) ghc/alloc 11,885,968,240 8,895,404,864 -25.2% GOOD ------------------------- Metric Decrease: MultiComponentModules MultiComponentModules100 MultiComponentModulesRecomp MultiComponentModulesRecomp100 ------------------------- - - - - - 28c819c9 by Rodrigo Mesquita at 2026-07-27T10:51:23+02:00 implicitRequirementsShallow can never reach HoleUnit findImportedModule will never return `HoleUnit` for a `ModuleName` (a `HoleUnit` can only be found as a signature instantiation, never as a directly *imported* thing) Therefore, we can drop `[ModuleName]` returned by `implicitRequirementsShallow`, which makes many things dead code. Namely, the call to `implicitRequirementsShallow` from GHC.Driver.Downsweep which was a performance bottleneck (for doing lots of duplicate work in findImportedModule) is now entirely gone. Fixes #27053 In an MR with this patch and the downsweep refactor (previous commit), CI says: MultiComponentModules(normal) ghc/alloc 2,097,396,728 1,943,662,304 -7.3% GOOD MultiComponentModules100(normal) ghc/alloc 24,310,182,136 17,227,574,440 -29.1% GOOD MultiComponentModulesRecomp(normal) ghc/alloc 602,769,518 449,973,656 -25.3% GOOD MultiComponentModulesRecomp100(normal) ghc/alloc 11,885,976,408 4,828,894,160 -59.4% GOOD and the Cabal test (building Cabal with ghc --make) improves in the total time reported by +RTS -s from 54s to 40s reliably on my machine with default+profiled_ghc flavour. That's a 25% reduction in total run time! ------------------------- Metric Decrease: MultiComponentModules MultiComponentModules100 MultiComponentModulesRecomp MultiComponentModulesRecomp100 ------------------------- - - - - - 35ddb38b by Rodrigo Mesquita at 2026-07-27T10:51:23+02:00 downsweep: Cache negative results When traversing a module graph structure, a uniquely identified node should always expand to the same thing. I don't see how visiting the same node which failed to be expanded a first time would ever successfully expand the second time we try to expand it (eg. when coming from a different edge to it -- it is still the same node!). The node expansion is local, based just based on the node itself, not on the path to get there. Therefore, this patch removes the weird behavior and commentary of `dfsBuild` wrt to `Nothing` not being cached and being potentially expanded a second time around to something different, which was misleading and, ultimately, incorrect. Now, we have a `MGRes`, which is more explicit about a node being Skipped just being a node that is ignored whenever it is found (and that skip is cached) -- and we may want to do this due to failures or due to just trying nodes which might not work on purpose, like hs-boots. We uniformly cache positive and negative results and remove the assumption that there might be an ordering in which the same node visited at a later time might be expanded differently. This makes it possible to traverse the module nodes in parallel without a change in behavior, since there's no longer a hidden ordering requirement. - - - - - 077678ca by Rodrigo Mesquita at 2026-07-27T10:51:23+02:00 Organize and clean-up GHC.Driver.Downsweep Simply some cosmetic changes, moving definitions around to structure the module better into its relevant sections (In go (ns ++ ss), it's not a problem to use ++ because it's a good producer and we won't have to append fully before processing the next item in go) - - - - - 7d089874 by Rodrigo Mesquita at 2026-07-27T10:51:23+02:00 fixup! Organize and clean-up GHC.Driver.Downsweep - - - - - 3ef8d34b by fendor at 2026-07-27T10:51:23+02:00 Fixup: fix note name - - - - - cf7de7aa by fendor at 2026-07-27T10:51:24+02:00 Fixup: changelog - - - - - 52f12516 by fendor at 2026-07-27T10:51:24+02:00 Fixup: remove redundant chagenlog.d entry - - - - - fca7e6e0 by fendor at 2026-07-27T10:51:24+02:00 Fixup: Update note references - - - - - 125 changed files: - .gitlab-ci.yml - + changelog.d/27532 - + changelog.d/T26716 - + changelog.d/downsweep-refactor - + changelog.d/warn-defaulted-callstack - compiler/GHC/Driver/Backpack.hs - compiler/GHC/Driver/Downsweep.hs - compiler/GHC/Driver/Env.hs - compiler/GHC/Driver/Flags.hs - compiler/GHC/Driver/Session.hs - compiler/GHC/Hs/Decls.hs - compiler/GHC/Hs/Instances.hs - compiler/GHC/Hs/Stats.hs - compiler/GHC/Hs/Utils.hs - compiler/GHC/HsToCore/Docs.hs - compiler/GHC/HsToCore/Quote.hs - compiler/GHC/Iface/Ext/Ast.hs - compiler/GHC/Parser/PostProcess.hs - compiler/GHC/Parser/PostProcess/Haddock.hs - compiler/GHC/Rename/Module.hs - compiler/GHC/Tc/Errors/Ppr.hs - compiler/GHC/Tc/Errors/Types.hs - compiler/GHC/Tc/Solver/Default.hs - compiler/GHC/Tc/Solver/Dict.hs - compiler/GHC/Tc/TyCl.hs - compiler/GHC/Tc/TyCl/Class.hs - compiler/GHC/Tc/Types/Evidence.hs - compiler/GHC/Tc/Types/Origin.hs - compiler/GHC/Tc/Utils/Backpack.hs - compiler/GHC/Tc/Utils/Unify.hs - compiler/GHC/ThToHs.hs - compiler/GHC/Types/Error/Codes.hs - compiler/GHC/Types/Unique/DFM.hs - compiler/GHC/Unit/Env.hs - compiler/Language/Haskell/Syntax/Binds.hs - compiler/Language/Haskell/Syntax/Decls.hs - docs/users_guide/eventlog-formats.rst - docs/users_guide/using-warnings.rst - libraries/base/changelog.md - libraries/base/src/GHC/Stack.hs - libraries/ghc-heap/GHC/Exts/Heap/FFIClosures_ProfilingDisabled.hsc - libraries/ghc-heap/GHC/Exts/Heap/FFIClosures_ProfilingEnabled.hsc - libraries/ghc-internal/src/GHC/Internal/Conc/Sync.hs - libraries/ghc-internal/src/GHC/Internal/Stack.hs - rts/IOManager.c - rts/IOManager.h - rts/Messages.c - rts/PrimOps.cmm - rts/RaiseAsync.c - rts/RaiseAsync.h - rts/STM.c - rts/Schedule.c - rts/StgMiscClosures.cmm - rts/Threads.c - rts/Trace.c - rts/Trace.h - rts/TraverseHeap.c - rts/include/Cmm.h - rts/include/rts/Constants.h - rts/include/rts/EventLogFormat.h - rts/include/rts/storage/TSO.h - rts/include/stg/MiscClosures.h - rts/posix/Poll.c - rts/posix/Select.c - rts/posix/Timeout.c - rts/sm/Compact.c - rts/sm/NonMovingMark.c - rts/sm/Sanity.c - rts/sm/Scav.c - rts/win32/AsyncMIO.c - testsuite/tests/ghc-api/fixed-nodes/FixedNodes.hs - testsuite/tests/ghc-api/fixed-nodes/InterfaceModuleGraph.hs - testsuite/tests/ghc-api/fixed-nodes/ModuleGraphInvariants.hs - testsuite/tests/ghci/T16793/T16793.stdout - testsuite/tests/ghci/T18060/T18060.stdout - + testsuite/tests/ghci/T27532/Makefile - + testsuite/tests/ghci/T27532/T27532.stdout - + testsuite/tests/ghci/T27532/T27532j4.stdout - + testsuite/tests/ghci/T27532/a.script - + testsuite/tests/ghci/T27532/all.T - + testsuite/tests/ghci/T27532/b.script - + testsuite/tests/ghci/T27532/genT27532Modules - testsuite/tests/ghci/scripts/ListTuplePunsPpr.stdout - testsuite/tests/ghci/scripts/T4175.stdout - testsuite/tests/ghci/scripts/T8469.stdout - testsuite/tests/ghci/scripts/T8535.stdout - testsuite/tests/ghci/scripts/T9881.stdout - testsuite/tests/ghci/scripts/ghci020.stdout - testsuite/tests/ghci/scripts/ghci064.stdout - testsuite/tests/ghci/should_run/T10145.stdout - testsuite/tests/ghci/should_run/T18594.stdout - testsuite/tests/haddock/haddock_examples/haddock.Test.stderr - testsuite/tests/haddock/should_compile_flag_haddock/T17544.stderr - testsuite/tests/haddock/should_compile_flag_haddock/T17544_kw.stderr - testsuite/tests/interface-stability/base-exports.stdout - testsuite/tests/interface-stability/base-exports.stdout-javascript-unknown-ghcjs - testsuite/tests/interface-stability/base-exports.stdout-mingw32 - testsuite/tests/parser/should_compile/DumpRenamedAst.stderr - testsuite/tests/parser/should_compile/DumpSemis.stderr - testsuite/tests/parser/should_compile/T20452.stderr - testsuite/tests/partial-sigs/should_compile/ExtraConstraints3.stderr - testsuite/tests/printer/Test24533.stdout - testsuite/tests/process/T3994.hs - testsuite/tests/roles/should_compile/Roles14.stderr - testsuite/tests/roles/should_compile/Roles3.stderr - testsuite/tests/roles/should_compile/Roles4.stderr - testsuite/tests/roles/should_compile/T8958.stderr - testsuite/tests/splice-imports/SI35.hs - testsuite/tests/typecheck/should_compile/T18406b.stderr - testsuite/tests/typecheck/should_compile/T18529.stderr - + testsuite/tests/typecheck/should_compile/WarnDefaultedCallStack.hs - + testsuite/tests/typecheck/should_compile/WarnDefaultedCallStack.stderr - testsuite/tests/typecheck/should_compile/all.T - testsuite/tests/typecheck/should_fail/T5300.stderr - utils/check-exact/ExactPrint.hs - utils/check-exact/Utils.hs - utils/check-ppr/Main.hs - utils/haddock/haddock-api/src/Haddock/Backends/Hoogle.hs - utils/haddock/haddock-api/src/Haddock/Backends/LaTeX.hs - utils/haddock/haddock-api/src/Haddock/Backends/Xhtml/Decl.hs - utils/haddock/haddock-api/src/Haddock/Convert.hs - utils/haddock/haddock-api/src/Haddock/GhcUtils.hs - utils/haddock/haddock-api/src/Haddock/Interface/Create.hs - utils/haddock/haddock-api/src/Haddock/Interface/Rename.hs - utils/haddock/haddock-api/src/Haddock/Types.hs The diff was not included because it is too large. View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/88c8b9461d57df7bb892bfc52ce44c… -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/88c8b9461d57df7bb892bfc52ce44c… You're receiving this email because of your account on gitlab.haskell.org. Manage all notifications: https://gitlab.haskell.org/-/profile/notifications | Help: https://gitlab.haskell.org/help

1 0