diff --git a/src/cmd/compile/internal/gc/inl.go b/src/cmd/compile/internal/gc/inl.go
index 60df4d06fd..85bbb4b4f3 100644
--- a/src/cmd/compile/internal/gc/inl.go
+++ b/src/cmd/compile/internal/gc/inl.go
@@ -363,7 +363,8 @@ func (v *hairyVisitor) visit(n *Node) bool {
 	case OIF:
 		if Isconst(n.Left, CTBOOL) {
 			// This if and the condition cost nothing.
-			return v.visitList(n.Nbody) || v.visitList(n.Rlist)
+			return v.visitList(n.Ninit) || v.visitList(n.Nbody) ||
+				v.visitList(n.Rlist)
 		}
 	}
 
diff --git a/test/fixedbugs/issue24120.go b/test/fixedbugs/issue24120.go
new file mode 100644
index 0000000000..6c7d871b76
--- /dev/null
+++ b/test/fixedbugs/issue24120.go
@@ -0,0 +1,14 @@
+// compile
+
+// Copyright 2018 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.
+
+package p
+
+var F func(int)
+
+func G() {
+	if F(func() int { return 1 }()); false {
+	}
+}