diff --git a/src/cmd/compile/internal/noder/transform.go b/src/cmd/compile/internal/noder/transform.go index ddbccf4ff4..50254e694a 100644 --- a/src/cmd/compile/internal/noder/transform.go +++ b/src/cmd/compile/internal/noder/transform.go @@ -730,11 +730,11 @@ func transformAppend(n *ir.CallExpr) ir.Node { assert(t.IsSlice()) if n.IsDDD { - if t.Elem().IsKind(types.TUINT8) && args[1].Type().IsString() { - return n - } - - args[1] = assignconvfn(args[1], t.Underlying()) + // assignconvfn is of args[1] not required here, as the + // types of args[0] and args[1] don't need to match + // (They will both have an underlying type which are + // slices of indentical base types, or be []byte and string.) + // See issue 53888. return n } diff --git a/src/cmd/compile/internal/test/issue53888_test.go b/src/cmd/compile/internal/test/issue53888_test.go new file mode 100644 index 0000000000..9f50a82a3c --- /dev/null +++ b/src/cmd/compile/internal/test/issue53888_test.go @@ -0,0 +1,44 @@ +// Copyright 2022 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. + +//go:build !race + +package test + +import ( + "testing" +) + +func TestAppendOfMake(t *testing.T) { + for n := 32; n < 33; n++ { // avoid stack allocation of make() + b := make([]byte, n) + f := func() { + b = append(b[:0], make([]byte, n)...) + } + if n := testing.AllocsPerRun(10, f); n > 0 { + t.Errorf("got %f allocs, want 0", n) + } + type S []byte + + s := make(S, n) + g := func() { + s = append(s[:0], make(S, n)...) + } + if n := testing.AllocsPerRun(10, g); n > 0 { + t.Errorf("got %f allocs, want 0", n) + } + h := func() { + s = append(s[:0], make([]byte, n)...) + } + if n := testing.AllocsPerRun(10, h); n > 0 { + t.Errorf("got %f allocs, want 0", n) + } + i := func() { + b = append(b[:0], make(S, n)...) + } + if n := testing.AllocsPerRun(10, i); n > 0 { + t.Errorf("got %f allocs, want 0", n) + } + } +} diff --git a/src/cmd/compile/internal/typecheck/func.go b/src/cmd/compile/internal/typecheck/func.go index 0988ce8dc7..7790e65ca2 100644 --- a/src/cmd/compile/internal/typecheck/func.go +++ b/src/cmd/compile/internal/typecheck/func.go @@ -465,7 +465,11 @@ func tcAppend(n *ir.CallExpr) ir.Node { return n } - args[1] = AssignConv(args[1], t.Underlying(), "append") + // AssignConv is of args[1] not required here, as the + // types of args[0] and args[1] don't need to match + // (They will both have an underlying type which are + // slices of indentical base types, or be []byte and string.) + // See issue 53888. return n } diff --git a/src/runtime/slice.go b/src/runtime/slice.go index 9ca0adefd8..75f202fca0 100644 --- a/src/runtime/slice.go +++ b/src/runtime/slice.go @@ -194,7 +194,7 @@ func growslice(et *_type, old slice, cap int) slice { } if cap < old.cap { - panic(errorString("growslice: cap out of range")) + panic(errorString("growslice: len out of range")) } if et.size == 0 { @@ -284,7 +284,7 @@ func growslice(et *_type, old slice, cap int) slice { // print(len(s), "\n") // } if overflow || capmem > maxAlloc { - panic(errorString("growslice: cap out of range")) + panic(errorString("growslice: len out of range")) } var p unsafe.Pointer diff --git a/test/fixedbugs/issue29190.go b/test/fixedbugs/issue29190.go index c0c4bb12b4..9f9b864eab 100644 --- a/test/fixedbugs/issue29190.go +++ b/test/fixedbugs/issue29190.go @@ -16,9 +16,9 @@ const maxInt = int(^uint(0) >> 1) func main() { s := make([]T, maxInt) - shouldPanic("cap out of range", func() { s = append(s, T{}) }) + shouldPanic("len out of range", func() { s = append(s, T{}) }) var oneElem = make([]T, 1) - shouldPanic("cap out of range", func() { s = append(s, oneElem...) }) + shouldPanic("len out of range", func() { s = append(s, oneElem...) }) } func shouldPanic(str string, f func()) {