diff --git a/core/oslib/oslib.h b/core/oslib/oslib.h
index 15f3709f5..7c7744bb9 100644
--- a/core/oslib/oslib.h
+++ b/core/oslib/oslib.h
@@ -46,8 +46,15 @@ namespace hostfs
 }
 
 #ifdef _WIN64
+#ifdef __MINGW64__
 struct _RUNTIME_FUNCTION;
+typedef struct _RUNTIME_FUNCTION RUNTIME_FUNCTION;
+#else
+struct _IMAGE_RUNTIME_FUNCTION_ENTRY;
+typedef struct _IMAGE_RUNTIME_FUNCTION_ENTRY RUNTIME_FUNCTION;
 #endif
+#endif
+
 class UnwindInfo
 {
 public:
@@ -63,7 +70,7 @@ public:
 private:
 	u8 *startAddr;
 #ifdef _WIN64
-	std::vector<_RUNTIME_FUNCTION *> tables;
+	std::vector<RUNTIME_FUNCTION *> tables;
 	std::vector<u16> codes;
 #endif
 #if defined(__unix__) || defined(__APPLE__)
diff --git a/core/windows/unwind_info.cpp b/core/windows/unwind_info.cpp
index da2e147f2..da79e384e 100644
--- a/core/windows/unwind_info.cpp
+++ b/core/windows/unwind_info.cpp
@@ -65,7 +65,7 @@ void UnwindInfo::endProlog(u32 offset)
 	codes.push_back(0);
 	std::reverse(codes.begin(), codes.end());
 	codes[0] = 1 | (offset  << 8);
-	codes[1] = codes.size() - 2;
+	codes[1] = (u8)codes.size() - 2;
 	if (codes.size() & 1)
 		codes.push_back(0);
 }