diff --git a/glide2x/cvg/glide/src/gerror.c b/glide2x/cvg/glide/src/gerror.c
index 9e560d0..0b8ae67 100644
--- a/glide2x/cvg/glide/src/gerror.c
+++ b/glide2x/cvg/glide/src/gerror.c
@@ -173,7 +173,7 @@ _grErrorDefaultCallback( const char *s, FxBool fatal )
   }
 }
 
-#ifdef __DOS__
+#if defined(__DOS__) && defined(__WATCOMC__)
 int _guHeapCheck( void )
 {
   int i = _heapchk();
diff --git a/glide2x/h3/glide/src/gerror.c b/glide2x/h3/glide/src/gerror.c
index d308106..fee129a 100644
--- a/glide2x/h3/glide/src/gerror.c
+++ b/glide2x/h3/glide/src/gerror.c
@@ -183,7 +183,7 @@ _grErrorDefaultCallback( const char *s, FxBool fatal )
   }
 }
 
-#ifdef __DOS__
+#if defined(__DOS__) && defined(__WATCOMC__)
 int _guHeapCheck( void )
 {
   int i = _heapchk();
diff --git a/glide2x/sst1/glide/src/gerror.c b/glide2x/sst1/glide/src/gerror.c
index 77c9f26..70a246f 100644
--- a/glide2x/sst1/glide/src/gerror.c
+++ b/glide2x/sst1/glide/src/gerror.c
@@ -134,7 +134,7 @@ _grErrorDefaultCallback( const char *s, FxBool fatal )
   }
 }
 
-#ifdef __DOS__
+#if defined(__DOS__) && defined(__WATCOMC__)
 int _guHeapCheck( void )
 {
   int i = _heapchk();