diff options
| author | Thiago Macieira <thiago.macieira@intel.com> | 2019-02-05 13:55:14 -0800 |
|---|---|---|
| committer | Thiago Macieira <thiago.macieira@intel.com> | 2019-02-06 08:11:29 +0000 |
| commit | 37352b23a90e9b4550b5a5cef175f2a77598faa0 (patch) | |
| tree | 214891c8ad94ea3de425e82b95457fab57e13de1 | |
| parent | b319d141105044f612ada1efe62685b2c5dd4514 (diff) | |
x86: Disable AVX support on 64-bit MinGW
GCC for 64-bit Windows has a bug that it fails to properly re-align the
stack pointer for use with 256-bit memory addresses (AVX). Therefore,
there's about a 50/50 chance that any function using AVX will have an
improperly-aligned stack. In release mode, stack accesses should be
rare, but in debug mode they happen frequently. Either way, this is a
ticking time bomb, so we disable.
Clang is not affected.
32-bit MinGW is not affected.
64-bit in other OSes with GCC are not affected.
Fixes: QTBUG-73539
Change-Id: Id061f35c088044b69a15fffd1580967808f31671
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>
| -rw-r--r-- | config.tests/x86_simd/main.cpp | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/config.tests/x86_simd/main.cpp b/config.tests/x86_simd/main.cpp index 8120cb9d3f..4fac13973a 100644 --- a/config.tests/x86_simd/main.cpp +++ b/config.tests/x86_simd/main.cpp @@ -144,6 +144,9 @@ attribute_target("sha") void test_shani() #endif #if T(AVX) +# if defined(__WIN64__) && defined(__GNUC__) && !defined(__clang__) +# error "AVX support is broken in 64-bit MinGW - https://gcc.gnu.org/bugzilla/show_bug.cgi?id=49001" +# endif attribute_target("avx") void test_avx() { __m256d a = _mm256_setzero_pd(); |