diff --git a/soltools/mkdepend/imakemdep.h b/soltools/mkdepend/imakemdep.h
index 6211da6c322d..36fd5b8666e4 100644
--- a/soltools/mkdepend/imakemdep.h
+++ b/soltools/mkdepend/imakemdep.h
@@ -566,7 +566,7 @@ struct pair predefs[] = {
 #ifdef __GNUC__
     {"__GNUC__", "1", NULL},
 #endif
-#if __STDC__
+#ifdef __STDC__
     {"__STDC__", "1", NULL},
 #endif
 #ifdef __HIGHC__