diff --git a/src/cmd/8g/cgen.c b/src/cmd/8g/cgen.c
index 0b2f2b76e9..f93be57e55 100644
--- a/src/cmd/8g/cgen.c
+++ b/src/cmd/8g/cgen.c
@@ -1055,7 +1055,7 @@ bgen(Node *n, int true, int likely, Prog *to)
 		}
 
 		if(is64(nr->type)) {
-			if(!nl->addable) {
+			if(!nl->addable || isconst(nl, CTINT)) {
 				tempname(&n1, nl->type);
 				cgen(nl, &n1);
 				nl = &n1;
diff --git a/test/fixedbugs/issue5002.go b/test/fixedbugs/issue5002.go
new file mode 100644
index 0000000000..1e74fa1a1f
--- /dev/null
+++ b/test/fixedbugs/issue5002.go
@@ -0,0 +1,16 @@
+// build
+
+// Copyright 2013 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Issue 5002: 8g produces invalid CMPL $0, $0.
+// Used to fail at link time.
+
+package main
+
+func main() {
+	var y int64
+	if y%1 == 0 {
+	}
+}