diff options
author | Cuong Manh Le <cuong.manhle.vn@gmail.com> | 2024-02-02 09:35:07 +0700 |
---|---|---|
committer | Gopher Robot <gobot@golang.org> | 2024-02-20 22:29:14 +0000 |
commit | 5428cc4f148bec34987781137ccd30494a99ad15 (patch) | |
tree | aca41e0e943051150d922ae1441a64b2aae504c3 | |
parent | 53708d86b076b7295e93e49b7a19ac7d9082044f (diff) | |
download | go-5428cc4f148bec34987781137ccd30494a99ad15.tar.gz go-5428cc4f148bec34987781137ccd30494a99ad15.zip |
cmd/compile/internal/typecheck: remove constant bounds check
types2 handles all constant-related bounds checks in user Go code now,
so it's safe to remove the check from typecheck, avoid the inconsistency
with type parameter.
Fixes #65417
Change-Id: I82dd197b78e271725d132b5a20450ae3e90f9abc
Reviewed-on: https://go-review.googlesource.com/c/go/+/560575
Reviewed-by: Keith Randall <khr@google.com>
Auto-Submit: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Robert Griesemer <gri@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
-rw-r--r-- | src/cmd/compile/internal/typecheck/expr.go | 13 | ||||
-rw-r--r-- | test/fixedbugs/issue65417.go | 42 |
2 files changed, 42 insertions, 13 deletions
diff --git a/src/cmd/compile/internal/typecheck/expr.go b/src/cmd/compile/internal/typecheck/expr.go index 12d1743874..eb9dc62d8a 100644 --- a/src/cmd/compile/internal/typecheck/expr.go +++ b/src/cmd/compile/internal/typecheck/expr.go @@ -621,19 +621,6 @@ func tcIndex(n *ir.IndexExpr) ir.Node { return n } - if !n.Bounded() && ir.IsConst(n.Index, constant.Int) { - x := n.Index.Val() - if constant.Sign(x) < 0 { - base.Errorf("invalid %s index %v (index must be non-negative)", why, n.Index) - } else if t.IsArray() && constant.Compare(x, token.GEQ, constant.MakeInt64(t.NumElem())) { - base.Errorf("invalid array index %v (out of bounds for %d-element array)", n.Index, t.NumElem()) - } else if ir.IsConst(n.X, constant.String) && constant.Compare(x, token.GEQ, constant.MakeInt64(int64(len(ir.StringVal(n.X))))) { - base.Errorf("invalid string index %v (out of bounds for %d-byte string)", n.Index, len(ir.StringVal(n.X))) - } else if ir.ConstOverflow(x, types.Types[types.TINT]) { - base.Errorf("invalid %s index %v (index too large)", why, n.Index) - } - } - case types.TMAP: n.Index = AssignConv(n.Index, t.Key(), "map index") n.SetType(t.Elem()) diff --git a/test/fixedbugs/issue65417.go b/test/fixedbugs/issue65417.go new file mode 100644 index 0000000000..15e84d819c --- /dev/null +++ b/test/fixedbugs/issue65417.go @@ -0,0 +1,42 @@ +// run + +// Copyright 2024 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 main + +import ( + "strings" + "unsafe" +) + +func main() { + shouldPanic("runtime error: index out of range", func() { f(0) }) + shouldPanic("runtime error: index out of range", func() { g(0) }) +} + +func f[T byte](t T) { + const str = "a" + _ = str[unsafe.Sizeof(t)] +} + +func g[T byte](t T) { + const str = "a" + _ = str[unsafe.Sizeof(t)+0] +} + +func shouldPanic(str string, f func()) { + defer func() { + err := recover() + if err == nil { + panic("did not panic") + } + s := err.(error).Error() + if !strings.Contains(s, str) { + panic("got panic " + s + ", want " + str) + } + }() + + f() +} |