diff --git a/desktop/wmclockmon/wmclockmon.SlackBuild b/desktop/wmclockmon/wmclockmon.SlackBuild
index d3e5d90dea..31acb3800a 100644
--- a/desktop/wmclockmon/wmclockmon.SlackBuild
+++ b/desktop/wmclockmon/wmclockmon.SlackBuild
@@ -69,7 +69,7 @@ find -L . \
  \( -perm 666 -o -perm 664 -o -perm 640 -o -perm 600 -o -perm 444 \
  -o -perm 440 -o -perm 400 \) -exec chmod 644 {} \;
 
-CFLAGS="$SLKCFLAGS" \
+CFLAGS="$SLKCFLAGS -fgnu89-inline" \
 CXXFLAGS="$SLKCFLAGS" \
 ./configure \
   --prefix=/usr \