diff --git a/support/functions/_cmd_build b/support/functions/_cmd_build
index 5d0e20b..3381a21 100644
--- a/support/functions/_cmd_build
+++ b/support/functions/_cmd_build
@@ -249,6 +249,9 @@ fi
 
 #link lastlog
 	ln -sf "$ldir/$log_name" "$workdir/lastbuild.log"
+	if [ ${USE_vars[USE_DIAG]} = "USE_DIAG=1" ]; then
+		grep -v "^CC\||\|LINK\|STRIP\|+\|^HOST\|^GEN\|___" >"$workdir/USE_DIAG.log" -i "$workdir/lastbuild.log"
+	fi
 
 #EXTRA_COPY_DIR
 	if [ $EXTRA_COPY_DIR -eq 1 ]; then