diff --git a/src/cmd/compile/internal/inline/inl.go b/src/cmd/compile/internal/inline/inl.go
index 817f2fd999..702b1d1cc5 100644
--- a/src/cmd/compile/internal/inline/inl.go
+++ b/src/cmd/compile/internal/inline/inl.go
@@ -304,7 +304,9 @@ func (v *hairyVisitor) doNode(n ir.Node) bool {
 						case "littleEndian.Uint64", "littleEndian.Uint32", "littleEndian.Uint16",
 							"bigEndian.Uint64", "bigEndian.Uint32", "bigEndian.Uint16",
 							"littleEndian.PutUint64", "littleEndian.PutUint32", "littleEndian.PutUint16",
-							"bigEndian.PutUint64", "bigEndian.PutUint32", "bigEndian.PutUint16":
+							"bigEndian.PutUint64", "bigEndian.PutUint32", "bigEndian.PutUint16",
+							"littleEndian.AppendUint64", "littleEndian.AppendUint32", "littleEndian.AppendUint16",
+							"bigEndian.AppendUint64", "bigEndian.AppendUint32", "bigEndian.AppendUint16":
 							cheap = true
 						}
 					}
diff --git a/test/inline_endian.go b/test/inline_endian.go
index e00e06a75e..fc94321de0 100644
--- a/test/inline_endian.go
+++ b/test/inline_endian.go
@@ -1,8 +1,6 @@
 // errorcheckwithauto -0 -m -d=inlfuncswithclosures=1
 
 //go:build (386 || amd64 || arm64 || ppc64le || s390x) && !gcflags_noopt
-// +build 386 amd64 arm64 ppc64le s390x
-// +build !gcflags_noopt
 
 // Copyright 2021 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
@@ -21,3 +19,17 @@ import (
 func endian(b []byte) uint64 { // ERROR "can inline endian" "b does not escape"
 	return binary.LittleEndian.Uint64(b) + binary.BigEndian.Uint64(b) // ERROR "inlining call to binary.littleEndian.Uint64" "inlining call to binary.bigEndian.Uint64"
 }
+
+func appendLittleEndian(b []byte) []byte { // ERROR "can inline appendLittleEndian" "leaking param: b to result ~r0 level=0"
+	b = binary.LittleEndian.AppendUint64(b, 64) // ERROR "inlining call to binary.littleEndian.AppendUint64"
+	b = binary.LittleEndian.AppendUint32(b, 32) // ERROR "inlining call to binary.littleEndian.AppendUint32"
+	b = binary.LittleEndian.AppendUint16(b, 16) // ERROR "inlining call to binary.littleEndian.AppendUint16"
+	return b
+}
+
+func appendBigEndian(b []byte) []byte { // ERROR "can inline appendBigEndian" "leaking param: b to result ~r0 level=0"
+	b = binary.BigEndian.AppendUint64(b, 64) // ERROR "inlining call to binary.bigEndian.AppendUint64"
+	b = binary.BigEndian.AppendUint32(b, 32) // ERROR "inlining call to binary.bigEndian.AppendUint32"
+	b = binary.BigEndian.AppendUint16(b, 16) // ERROR "inlining call to binary.bigEndian.AppendUint16"
+	return b
+}