__GNUC__ is #defined when building with mingw.

Heesterman, Peter J · Heesterman, Peter J · commit ab5b0e560864 · 2022-05-30T14:29:57.000+01:00
But we still want to use win32/pthread
diff --git a/supportApp/bloscSrc/blosc/blosc.c b/supportApp/bloscSrc/blosc/blosc.c
@@ -54,7 +54,7 @@
   #include <inttypes.h>
 #endif  /* _WIN32 */
 
-#if defined(_WIN32) && !defined(__GNUC__)
+#if defined(_WIN32)
   #include "win32/pthread.h"
   #include "win32/pthread.c"
 #else
