go/test/fixedbugs/issue28085.go
Matthew Dempsky 6fa7669fd7 cmd/compile: unify duplicate const detection logic
Consistent logic for handling both duplicate map keys and case values,
and eliminates ad hoc value hashing code.

Also makes cmd/compile consistent with go/types's handling of
duplicate constants (see #28085), which is at least an improvement
over the status quo even if we settle on something different for the
spec.

As a side effect, this also suppresses cmd/compile's warnings about
duplicate nils in (non-interface expression) switch statements, which
was technically never allowed by the spec anyway.

Updates #28085.
Updates #28378.

Change-Id: I176a251e770c3c5bc11c2bf8d1d862db8f252a17
Reviewed-on: https://go-review.googlesource.com/c/152544
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2019-02-27 01:08:13 +00:00

30 lines
490 B
Go

// errorcheck
// 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 _ = map[interface{}]int{
0: 0,
0: 0, // ERROR "duplicate"
}
var _ = map[interface{}]int{
interface{}(0): 0,
interface{}(0): 0, // ok
}
func _() {
switch interface{}(0) {
case 0:
case 0: // ERROR "duplicate"
}
switch interface{}(0) {
case interface{}(0):
case interface{}(0): // ok
}
}