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Marge Bot pushed to branch master at Glasgow Haskell Compiler / GHC

Commits:

867c2675

by Cheng Shao at 2025-09-20T06:49:28-04:00

wasm: fix dyld handling for forward declared GOT.func items

This patch fixes wasm shared linker's handling of forward declared
GOT.func items, see linked issue for details. Also adds T26430 test to
witness the fix. Fixes #26430.

Co-authored-by: Codex <codex@openai.com>

6 changed files:

+ testsuite/tests/ghci-wasm/Makefile
+ testsuite/tests/ghci-wasm/T26430.hs
+ testsuite/tests/ghci-wasm/T26430A.c
+ testsuite/tests/ghci-wasm/T26430B.c
+ testsuite/tests/ghci-wasm/all.T
utils/jsffi/dyld.mjs

Changes:

testsuite/tests/ghci-wasm/Makefile

 +TOP=../..
 +include $(TOP)/mk/boilerplate.mk
 +include $(TOP)/mk/test.mk
++
 +T26430_setup :
 +	'$(TEST_HC)' $(TEST_HC_OPTS) $(ghciWayFlags) -shared T26430A.c -o libT26430A.so
 +	'$(TEST_HC)' $(TEST_HC_OPTS) $(ghciWayFlags) -shared -L. -lT26430A T26430B.c -o libT26430B.so

testsuite/tests/ghci-wasm/T26430.hs

+foreign import ccall unsafe "baz" main :: IO ()

testsuite/tests/ghci-wasm/T26430A.c

 +void foo(void);
++
 +void bar(void (*)(void));
++
 +__attribute__((export_name("baz"))) void baz(void) { bar(foo); }

testsuite/tests/ghci-wasm/T26430B.c

 +__attribute__((export_name("foo"))) void foo(void) {}
++
 +__attribute__((export_name("bar"))) void bar(void (*f)(void)) { f(); }

testsuite/tests/ghci-wasm/all.T

 +setTestOpts([
 +  unless(arch('wasm32'), skip),
 +  only_ways(['ghci', 'ghci-opt']),
 +  extra_ways(['ghci', 'ghci-opt'])
 +])
++
 +test('T26430', [
 +  extra_files(['T26430A.c', 'T26430B.c']),
 +  pre_cmd('$MAKE -s --no-print-directory T26430_setup ghciWayFlags=' + config.ghci_way_flags),
 +  extra_hc_opts('-L. -lT26430B')]
 +, compile_and_run, ['']
 +)

utils/jsffi/dyld.mjs

@@ -1013,10 +1013,13 @@ class DyLD {
            // anything, if it's required later a GOT.func entry will be
            // created on demand.
            if (this.#gotFunc[k]) {
 -            // ghc-prim/ghc-internal may export functions imported by
 -            // rts
 -            console.assert(this.#gotFunc[k].value === DyLD.#poison);
 -            this.#table.set(this.#gotFunc[k].value, v);
 +            const got = this.#gotFunc[k];
 +            if (got.value === DyLD.#poison) {
 +              const idx = this.#table.grow(1, v);
 +              got.value = idx;
 +            } else {
 +              this.#table.set(got.value, v);
 +            }
+           }
            continue;
+         }