Merge pull request #130 from hyc/gccwin32

Fix for win32 build with gcc

src/instructions_portable.cpp

@@ -161,7 +161,7 @@ void rx_set_rounding_mode(uint32_t mode) {
 
 #ifdef RANDOMX_USE_X87
 
-#ifdef _M_IX86
+#if defined(_MSC_VER) && defined(_M_IX86)
 
 void rx_set_double_precision() {
 	_control87(_PC_53, _MCW_PC);

src/intrin_portable.h

@@ -61,7 +61,7 @@ constexpr int RoundToZero = 3;
 //the library "sqrt" function provided by MSVC for x86 targets doesn't give
 //the correct results, so we have to use inline assembly to call x87 fsqrt directly
 #if !defined(__SSE2__)
-#if defined(_M_IX86)
+#if defined(_MSC_VER) && defined(_M_IX86)
 inline double __cdecl rx_sqrt(double x) {
 	__asm {
 		fld x