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#21 call asan on setjmp #22

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#21 call asan on setjmp #22

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6c995b4
#21 call asan on setjmp
balupillai Apr 2, 2026
00599c2
#21 call asan on setjmp
balupillai Apr 2, 2026
b861a77
#21 call asan on setjmp
balupillai Apr 2, 2026
27c45ad
#lua-21 cleanup
balupillai Apr 14, 2026
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10 changes: 9 additions & 1 deletion src/thrlua.h
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Original file line number Diff line number Diff line change
Expand Up @@ -218,7 +218,15 @@ struct lua_longjmp {
# define LUA_ASMNAME(x) _##x
#endif

#if LUA_ARCH_X86_64
/*
** Under AddressSanitizer, use system setjmp/longjmp so ASAN can
** intercept them and properly unpoison skipped stack frames.
** The custom asm versions bypass ASAN and cause false positives.
*/
#if defined(__SANITIZE_ADDRESS__)
# define lua_do_setjmp setjmp
# define lua_do_longjmp longjmp
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@cursor cursor bot Apr 14, 2026

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ASAN detection misses Clang before version 21

Low Severity

The ASAN check uses only __SANITIZE_ADDRESS__, which GCC has supported since 4.8 but Clang only added in version 21 (2026). Clang versions before 21 use __has_feature(address_sanitizer) instead. Builds with older Clang and -fsanitize=address will silently skip this block and continue using the custom asm setjmp/longjmp, defeating the purpose of the ASAN fix. The common portable pattern checks both: defined(__SANITIZE_ADDRESS__) || (defined(__has_feature) && __has_feature(address_sanitizer)).

Fix in Cursor Fix in Web

Reviewed by Cursor Bugbot for commit 27c45ad. Configure here.

#elif LUA_ARCH_X86_64
# define lua_do_setjmp LUA_ASMNAME(lua_setjmp_amd64)
# define lua_do_longjmp LUA_ASMNAME(lua_longjmp_amd64)
#elif LUA_ARCH_I386
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