From 9d90388247e093cd9b3ead79954df2ac18bfeb66 Mon Sep 17 00:00:00 2001 From: Magnus Hagander Date: Thu, 10 Mar 2016 13:48:58 +0100 Subject: [PATCH] Avoid crash on old Windows with AVX2-capable CPU for VS2013 builds The Visual Studio 2013 CRT generates invalid code when it makes a 64-bit build that is later used on a CPU that supports AVX2 instructions using a version of Windows before 7SP1/2008R2SP1. Detect this combination, and in those cases turn off the generation of FMA3, per recommendation from the Visual Studio team. The bug is actually in the CRT shipping with Visual Studio 2013, but Microsoft have stated they're only fixing it in newer major versions. The fix is therefor conditioned specifically on being built with this version of Visual Studio, and not previous or later versions. Author: Christian Ullrich --- src/backend/main/main.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/src/backend/main/main.c b/src/backend/main/main.c index 19176b1b17..020c8939de 100644 --- a/src/backend/main/main.c +++ b/src/backend/main/main.c @@ -26,6 +26,11 @@ #include #endif +#if defined(_M_AMD64) && _MSC_VER == 1800 +#include +#include +#endif + #include "bootstrap/bootstrap.h" #include "common/username.h" #include "postmaster/postmaster.h" @@ -263,6 +268,22 @@ startup_hacks(const char *progname) /* In case of general protection fault, don't show GUI popup box */ SetErrorMode(SEM_FAILCRITICALERRORS | SEM_NOGPFAULTERRORBOX); + +#if defined(_M_AMD64) && _MSC_VER == 1800 + /* + * Avoid crashing in certain floating-point operations if + * we were compiled for x64 with MS Visual Studio 2013 and + * are running on Windows prior to 7/2008R2 SP1 on an + * AVX2-capable CPU. + * + * Ref: https://connect.microsoft.com/VisualStudio/feedback/details/811093/visual-studio-2013-rtm-c-x64-code-generation-bug-for-avx2-instructions + */ + if (!IsWindows7SP1OrGreater()) + { + _set_FMA3_enable(0); + } +#endif /* defined(_M_AMD64) && _MSC_VER == 1800 */ + } #endif /* WIN32 */ -- 2.40.0