mirror of
https://github.com/golang/go
synced 2024-11-26 18:26:48 -07:00
259fd8adbb
In the previous CL, I had incorrectly removed one of the error messages from issue20232.go, because I thought go/constant was just handling it. But actually the compiler was panicking in nodlit, because it didn't handle constant.Unknown. So this CL makes it leave n.Type == nil for unknown constant.Values. While here, also address #42732 by making sure to report an error message when origConst is called with an unknown constant.Value (as can happen when multiplying two floating-point constants overflows). Finally, add OXOR and OBITNOT to the list of operations to report errors about, since they're also constant expressions that can produce a constant with a greater bit length than their operands. Fixes #42732. Change-Id: I4a538fbae9b3ac4c553d7de5625dc0c87d9acce3 Reviewed-on: https://go-review.googlesource.com/c/go/+/272928 Trust: Matthew Dempsky <mdempsky@google.com> Run-TryBot: Matthew Dempsky <mdempsky@google.com> TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Russ Cox <rsc@golang.org>
33 lines
972 B
Go
33 lines
972 B
Go
// errorcheck
|
|
|
|
// Copyright 2009 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.
|
|
|
|
// Verify that large integer constant expressions cause overflow.
|
|
// Does not compile.
|
|
|
|
package main
|
|
|
|
const (
|
|
A int = 1
|
|
B byte; // ERROR "type without expr|expected .=."
|
|
)
|
|
|
|
const LargeA = 1000000000000000000
|
|
const LargeB = LargeA * LargeA * LargeA
|
|
const LargeC = LargeB * LargeB * LargeB // GC_ERROR "constant multiplication overflow"
|
|
|
|
const AlsoLargeA = LargeA << 400 << 400 >> 400 >> 400 // GC_ERROR "constant shift overflow"
|
|
|
|
// Issue #42732.
|
|
|
|
const a = 1e+500000000
|
|
const b = a * a // ERROR "constant multiplication overflow"
|
|
const c = b * b
|
|
|
|
const MaxInt512 = (1<<256 - 1) * (1<<256 + 1)
|
|
const _ = MaxInt512 + 1 // ERROR "constant addition overflow"
|
|
const _ = MaxInt512 ^ -1 // ERROR "constant bitwise XOR overflow"
|
|
const _ = ^MaxInt512 // ERROR "constant bitwise complement overflow"
|