diff --git a/cmd/vet/atomic.go b/cmd/vet/atomic.go
index dfe3f03c..a71a6920 100644
--- a/cmd/vet/atomic.go
+++ b/cmd/vet/atomic.go
@@ -44,6 +44,9 @@ func (f *File) checkAtomicAssignment(n *ast.AssignStmt) {
 // checkAtomicAddAssignment walks the atomic.Add* method calls checking for assigning the return value
 // to the same variable being used in the operation
 func (f *File) checkAtomicAddAssignment(left ast.Expr, call *ast.CallExpr) {
+	if len(call.Args) != 2 {
+		return
+	}
 	arg := call.Args[0]
 	broken := false
 
diff --git a/cmd/vet/testdata/atomic.go b/cmd/vet/testdata/atomic.go
index 7a6dcb8c..1ba261d9 100644
--- a/cmd/vet/testdata/atomic.go
+++ b/cmd/vet/testdata/atomic.go
@@ -38,4 +38,6 @@ func AtomicTests() {
 	ap := []*uint64{&au[0], &au[1]}
 	*ap[0] = atomic.AddUint64(ap[0], 1) // ERROR "direct assignment to atomic value"
 	*ap[1] = atomic.AddUint64(ap[0], 1)
+
+	x = atomic.AddUint64() // Used to make vet crash; now silently ignored.
 }