diff --git a/Source/GSNetwork.h b/Source/GSNetwork.h
index a6abcc159..15c18830d 100644
--- a/Source/GSNetwork.h
+++ b/Source/GSNetwork.h
@@ -38,7 +38,7 @@
 #include <sys/stat.h>
 #include <fcntl.h>
 
-#if     defined(__MINGW__)
+#if     defined(__MINGW32__) || defined(__MINGW64__)
 
 #include <io.h>
 #include <winsock2.h>
diff --git a/Source/ObjectiveC2/blocks_runtime.m b/Source/ObjectiveC2/blocks_runtime.m
index 55cf15394..d152ff4a8 100644
--- a/Source/ObjectiveC2/blocks_runtime.m
+++ b/Source/ObjectiveC2/blocks_runtime.m
@@ -200,7 +200,7 @@ struct StackBlockClass {
   const char *types;
 };
 
-#if	defined(__MINGW__)
+#if	defined(__MINGW32__) || defined(__MINGW64__)
 /* FIXME ... evil hack ... declare symbol to avoid linker error on windows
  * where the compiler/linker doesn't support a weak reference.
  * This obviously breaks the code below...
diff --git a/Tools/gdomap.c b/Tools/gdomap.c
index 38ca87b98..e5341b924 100644
--- a/Tools/gdomap.c
+++ b/Tools/gdomap.c
@@ -26,6 +26,12 @@
 
 #include "config.h"
 
+#if	!defined(__MINGW__)
+#  if	defined(__MINGW32__) || defined(__MINGW64__)
+#    define	__MINGW__
+#  endif
+#endif
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdarg.h>