From 8daaac8e10f68289b44f68d0925e169176ce8a5c Mon Sep 17 00:00:00 2001
From: Jia Tan <jiat0218@gmail.com>
Date: Thu, 19 Jan 2023 20:35:09 +0800
Subject: [PATCH] tuklib_physmem: Silence warning from -Wcast-function-type on
 MinGW-w64.

tuklib_physmem depends on GetProcAddress() for both MSVC and MinGW-w64
to retrieve a function address. The proper way to do this is to cast the
return value to the type of function pointer retrieved. Unfortunately,
this causes a cast-function-type warning, so the best solution is to
simply ignore the warning.
---
 src/common/tuklib_physmem.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/src/common/tuklib_physmem.c b/src/common/tuklib_physmem.c
index a1bccb2f..69f6fd4c 100644
--- a/src/common/tuklib_physmem.c
+++ b/src/common/tuklib_physmem.c
@@ -73,6 +73,17 @@
 #endif
 
 
+// With GCC >= 8.1 with -Wextra and Clang >= 13 with -Wcast-function-type
+// will warn about the Windows-specific code.
+#if defined(__has_warning)
+#	if __has_warning("-Wcast-function-type")
+#		define CAN_DISABLE_WCAST_FUNCTION_TYPE 1
+#	endif
+#elif TUKLIB_GNUC_REQ(8,1)
+#	define CAN_DISABLE_WCAST_FUNCTION_TYPE 1
+#endif
+
+
 extern uint64_t
 tuklib_physmem(void)
 {
@@ -87,8 +98,15 @@ tuklib_physmem(void)
 		HMODULE kernel32 = GetModuleHandle(TEXT("kernel32.dll"));
 		if (kernel32 != NULL) {
 			typedef BOOL (WINAPI *gmse_type)(LPMEMORYSTATUSEX);
+#ifdef CAN_DISABLE_WCAST_FUNCTION_TYPE
+#	pragma GCC diagnostic push
+#	pragma GCC diagnostic ignored "-Wcast-function-type"
+#endif
 			gmse_type gmse = (gmse_type)GetProcAddress(
 					kernel32, "GlobalMemoryStatusEx");
+#ifdef CAN_DISABLE_WCAST_FUNCTION_TYPE
+#	pragma GCC diagnostic pop
+#endif
 			if (gmse != NULL) {
 				MEMORYSTATUSEX meminfo;
 				meminfo.dwLength = sizeof(meminfo);