#10533: Typechecker behaves differently on Phab and on Mac -------------------------------------+------------------------------------- Reporter: goldfire | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.11 Resolution: | Keywords: Operating System: MacOS X | Architecture: Type of failure: None/Unknown | Unknown/Multiple Blocked By: | Test Case: Related Tickets: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- Comment (by simonpj): Bizarre. This is with HEAD? Can you compile FD3 with `-ddump-tc-trace` on your Mac and attach the results? Simon -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10533#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#10533: Typechecker behaves differently on Phab and on Mac -------------------------------------+------------------------------------- Reporter: goldfire | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.11 Resolution: | Keywords: Operating System: MacOS X | Architecture: Type of failure: None/Unknown | Unknown/Multiple Blocked By: | Test Case: Related Tickets: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- Comment (by goldfire): Just rebuilt on a different Mac (both with MacOS 10.8.5) from scratch with the same behavior. Here is an excerpt: {{{ 10:40:42 ~/Documents/Programming/ghc- cur/testsuite/tests/typecheck/should_compile> git log -n 1 commit 61b96a86c5342fb1c850361177d60fe855d948f6 Author: Richard Eisenberg Date: Fri Jun 5 09:56:21 2015 -0400 Fix #10489 Dang, roles are annoying. Test case: typecheck/should_compile/T10489 10:40:45 ~/Documents/Programming/ghc- cur/testsuite/tests/typecheck/should_compile> ~/Documents/Programming/ghc- cur/inplace/bin/ghc-stage2 --version The Glorious Glasgow Haskell Compilation System, version 7.11.20150605 10:40:53 ~/Documents/Programming/ghc- cur/testsuite/tests/typecheck/should_compile> ~/Documents/Programming/ghc- cur/inplace/bin/ghc-stage2 -ddump-tc-trace FD3.hs > ~/temp/FD3.log 2>&1 10:41:26 ~/Documents/Programming/ghc- cur/testsuite/tests/typecheck/should_compile> }}} The trace is attached. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10533#comment:3 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#10533: Typechecker behaves differently on Phab and on Mac -------------------------------------+------------------------------------- Reporter: goldfire | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.11 Resolution: | Keywords: Operating System: MacOS X | Architecture: Type of failure: None/Unknown | Unknown/Multiple Blocked By: | Test Case: Related Tickets: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- Comment (by rwbarton): Attached. Your output seems to have additional messages that are enabled when `debugIsOn`, so maybe some other debugging output or assertion is panicking for you? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10533#comment:5 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#10533: Assertion failure on FD3 test in TcErrors -------------------------------------+------------------------------------- Reporter: goldfire | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler (Type | Version: 7.11 checker) | Keywords: Resolution: | Architecture: Operating System: Unknown/Multiple | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Revisions: -------------------------------------+------------------------------------- Changes (by goldfire): * os: MacOS X => Unknown/Multiple * component: Compiler => Compiler (Type checker) Old description:

On my Mac, commit 61b96a86c5342fb1c850361177d60fe855d948f6 causes test `typecheck/should_compile/FD3` to fail. But Phab succeeded in validating this commit, as seen [https://phabricator.haskell.org/B4297 here]. (I don't believe that commit has anything to do with the failure -- it's just the snapshot I looked at.)

This leads to two questions:

1. Why does this test fail on a Mac?

2. Why does the typechecker behave differently, at all, on two different platforms?

New description: Test case `typecheck/should_compile/FD3` leads to an `ASSERT`ion error: {{{ ghc-stage2: panic! (the 'impossible' happened) (GHC version 7.11.20150605 for x86_64-apple-darwin): ASSERT failed! file compiler/typecheck/TcErrors.hs line 321 [[D] _ :: a_amP[sk] ~ (String, a_amP[sk]) (CNonCanonical)] Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug }}} FD3.log (attached) shows the error happening. (When originally posting this ticket, I was very confused. The first several comments, through comment:6, are now bogus. Please ignore.) -- -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10533#comment:7 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler