Fix regressions: build with VS2005 / older SDKs

dispserv_win32.c: provide QDC_DATABASE_CURRENT fallback for SDKs
predating the Win7 CCD APIs. The runtime symbols are loaded via
GetProcAddress when HAVE_DYLIB is set, so only the constant is missing.

vfs_implementation.c: in retro_vfs_stat_impl LEGACY_WIN32 branch, call
_stat64 explicitly instead of the bare _stat macro. The macro expands
to _stat64i32 on VS2005+, mismatching the declared 'struct _stat64'
buffer and silently truncating st_size for files >= 2 GiB. Falls back
to _stati64 on VC6.

Author: LibretroAdmin

gfx/display_servers/dispserv_win32.c

@@ -29,6 +29,16 @@
 #define _WIN32_WINDOWS 0x0601
 #endif
 
+/* QueryDisplayConfig and friends are Windows 7+. The SDK shipped
+ * with VS2005 (and some older mingw-w64 versions) does not declare
+ * QDC_DATABASE_CURRENT, even though the runtime symbols are loaded
+ * via GetProcAddress when HAVE_DYLIB is set. Provide a fallback so
+ * the code compiles on those toolchains; on a modern SDK this is a
+ * no-op since the symbol is already defined in wingdi.h. */
+#ifndef QDC_DATABASE_CURRENT
+#define QDC_DATABASE_CURRENT 0x00000004
+#endif
+
 /* VC6 needs objbase included before initguid, but nothing else does */
 #include <objbase.h>
 #include <initguid.h>

libretro-common/vfs/vfs_implementation.c

@@ -1136,8 +1136,20 @@ int retro_vfs_stat_64_impl(const char *path, int64_t *size)
 
       file_info                 = GetFileAttributes(path_local);
 
+      /* Use _stat64 explicitly to match the struct _stat64 buffer
+       * declared above. The bare _stat is a macro that expands to
+       * _stat64i32 on VS2005+ (or _stat32 with _USE_32BIT_TIME_T),
+       * neither of which match struct _stat64 -- passing the wrong
+       * struct silently truncates st_size. _stat64 has been in MSVC
+       * since VS2003 (_MSC_VER >= 1300) and is provided by mingw-w64.
+       * VC6 has no 64-bit time_t at all; _stati64 is the only match. */
+#if defined(_MSC_VER) && _MSC_VER < 1300
       if (file_info == INVALID_FILE_ATTRIBUTES
-            || _stat(path_local, &stat_buf) != 0)
+            || _stati64(path_local, (struct _stati64*)&stat_buf) != 0)
+#else
+      if (file_info == INVALID_FILE_ATTRIBUTES
+            || _stat64(path_local, &stat_buf) != 0)
+#endif
       {
          free(path_local);
          return 0;