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| author | lhchavez <lhchavez@lhchavez.com> | 2020-12-18 07:03:21 -0800 |
|---|---|---|
| committer | lhchavez <lhchavez@lhchavez.com> | 2020-12-18 07:07:56 -0800 |
| commit | 7f8ae01913e408bf219ab41036bd68265596c917 (patch) | |
| tree | aedd0050f92c010300bdfed0114f4141409815ee | |
| parent | 530d37beb2731a2073f5298242825a803815c37c (diff) | |
| download | libgit2-7f8ae01913e408bf219ab41036bd68265596c917.tar.gz | |
Avoid using `__builtin_mul_overflow` with the clang+32-bit combo
This causes clang to produce an undefined reference to `__mulodi4`. This
could be fixed by statically linking some compiler-rt libraries to
provide this symbol, but let's first stop the bleeding since doing the
correct long-term fix requires some non-trivial CMake knowledge which I
lack.
| -rw-r--r-- | src/integer.h | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/src/integer.h b/src/integer.h index 026a1fac0..28122a99f 100644 --- a/src/integer.h +++ b/src/integer.h @@ -79,8 +79,12 @@ GIT_INLINE(int) git__is_int(long long p) # define git__add_int64_overflow(out, one, two) \ __builtin_add_overflow(one, two, out) -# define git__multiply_int64_overflow(out, one, two) \ - __builtin_mul_overflow(one, two, out) + +/* clang on 32-bit systems produces an undefined reference to `__mulodi4`. */ +# if !defined(__clang__) || !defined(GIT_ARCH_32) +# define git__multiply_int64_overflow(out, one, two) \ + __builtin_mul_overflow(one, two, out) +# endif /* Use Microsoft's safe integer handling functions where available */ #elif defined(_MSC_VER) @@ -156,6 +160,10 @@ GIT_INLINE(bool) git__add_int64_overflow(int64_t *out, int64_t one, int64_t two) return false; } +#endif + +/* If we could not provide an intrinsic implementation for this, provide a (slow) fallback. */ +#if !defined(git__multiply_int64_overflow) GIT_INLINE(bool) git__multiply_int64_overflow(int64_t *out, int64_t one, int64_t two) { if ((one == -1 && two == INT_MIN) || @@ -166,7 +174,6 @@ GIT_INLINE(bool) git__multiply_int64_overflow(int64_t *out, int64_t one, int64_t *out = one * two; return false; } - #endif #endif |