diff --git a/src/cmd/gc/const.c b/src/cmd/gc/const.c
index a22cbbc130..c44a2a6b74 100644
--- a/src/cmd/gc/const.c
+++ b/src/cmd/gc/const.c
@@ -143,6 +143,9 @@ evconst(Node *n)
 	Mpint *xval;
 	Mpflt *fval;
 
+	xval = nil;
+	fval = nil;
+
 	nl = n->left;
 	if(nl == N)
 		return;