diff --git a/mingw-w64-libraries/winpthreads/src/thread.c b/mingw-w64-libraries/winpthreads/src/thread.c
index d5b3aaa..742a022 100644
--- a/mingw-w64-libraries/winpthreads/src/thread.c
+++ b/mingw-w64-libraries/winpthreads/src/thread.c
@@ -1522,7 +1522,7 @@
 
 #if defined(__i386__)
 /* Align ESP on 16-byte boundaries. */
-#  if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 2)
+#  if defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 2))
 __attribute__((force_align_arg_pointer))
 #  endif
 #endif