diff --git a/configure.ac b/configure.ac
index ceeb9de575..e33b6c79c0 100644
--- a/configure.ac
+++ b/configure.ac
@@ -867,7 +867,7 @@ AC_RUN_IFELSE(
 	[AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT],
 		[[
 		FILE *f = fopen(".", "r");
-		return f)]])],
+		return f != NULL;]])],
 	[ac_cv_fread_reads_directories=no],
 	[ac_cv_fread_reads_directories=yes])
 ])