diff --git a/stb_image.h b/stb_image.h index c3945c2..2af8e3a 100644 --- a/stb_image.h +++ b/stb_image.h @@ -624,7 +624,12 @@ typedef unsigned char validate_uint32[sizeof(stbi__uint32)==4 ? 1 : -1]; #define STBI_FREE(p) free(p) #endif -#if defined(__GNUC__) && !defined(__SSE2__) && !defined(STBI_NO_SIMD) +// x86/x64 detection +#if defined(__x86_64__) || defined(_M_X64) || defined(__i386) || defined(_M_IX86) +#define STBI_X86_TARGET +#endif + +#if defined(__GNUC__) && defined(STBI_X86_TARGET) && !defined(__SSE2__) && !defined(STBI_NO_SIMD) // gcc doesn't support sse2 intrinsics unless you compile with -msse2, // (but compiling with -msse2 allows the compiler to use SSE2 everywhere; // this is just broken and gcc are jerks for not fixing it properly @@ -632,7 +637,20 @@ typedef unsigned char validate_uint32[sizeof(stbi__uint32)==4 ? 1 : -1]; #define STBI_NO_SIMD #endif -#if !defined(STBI_NO_SIMD) && (defined(__x86_64__) || defined(_M_X64) || defined(__i386) || defined(_M_IX86)) +#if defined(__MINGW32__) && defined(STBI_X86_TARGET) && !defined(STBI_MINGW_ENABLE_SSE2) && !defined(STBI_NO_SIMD) +// 32-bit MinGW wants ESP to be 16-byte aligned, but this is not in the +// Windows ABI and VC++ as well as Windows DLLs don't maintain that invariant. +// As a result, enabling SSE2 on 32-bit MinGW is dangerous when not +// simultaneously enabling "-mstackrealign". +// +// See https://github.com/nothings/stb/issues/81 for more information. +// +// So default to no SSE2 on 32-bit MinGW. If you've read this far and added +// -mstackrealign to your build settings, feel free to #define STBI_MINGW_ENABLE_SSE2. +#define STBI_NO_SIMD +#endif + +#if !defined(STBI_NO_SIMD) && defined(STBI_X86_TARGET) #define STBI_SSE2 #include