diff --git a/src/cmd/6g/ggen.c b/src/cmd/6g/ggen.c
index 06b0f8003f1..b92d24ebcd8 100644
--- a/src/cmd/6g/ggen.c
+++ b/src/cmd/6g/ggen.c
@@ -557,13 +557,15 @@ cgen_shift(int op, Node *nl, Node *nr, Node *res)
 	Node n1, n2, n3;
 	int a;
 	Prog *p1;
+	uvlong sc;
 
 	a = optoas(op, nl->type);
 
 	if(nr->op == OLITERAL) {
 		regalloc(&n1, nl->type, res);
 		cgen(nl, &n1);
-		if(mpgetfix(nr->val.u.xval) >= nl->type->width*8) {
+		sc = mpgetfix(nr->val.u.xval);
+		if(sc >= nl->type->width*8) {
 			// large shift gets 2 shifts by width
 			nodconst(&n3, types[TUINT32], nl->type->width*8-1);
 			gins(a, &n3, &n1);
diff --git a/test/bugs/bug155.go b/test/fixedbugs/bug155.go
similarity index 100%
rename from test/bugs/bug155.go
rename to test/fixedbugs/bug155.go
diff --git a/test/golden.out b/test/golden.out
index 98348e753a6..46b4fb22099 100644
--- a/test/golden.out
+++ b/test/golden.out
@@ -104,12 +104,6 @@ BUG should compile
 5 7
 BUG: should crash
 
-=========== bugs/bug155.go
-main·f: doasm: notfound from=75 to=13 (82)    SHLQ    $-9223372036854775808,BX
-main·f: doasm: notfound from=75 to=13 (82)    SHLQ    $-9223372036854775808,BX
-main·f: doasm: notfound from=75 to=13 (82)    SHLQ    $-9223372036854775808,BX
-BUG: bug155
-
 =========== bugs/bug156.go
 bugs/bug156.go:7: constant 18446744073709551615 overflows int64
 BUG: bug156