code review 11879044: [release-branch.go1.1] cmd/gc: avoid passing unevaluate...

[release-branch.go1.1] cmd/gc: avoid passing unevaluated constant expressions to backends.

««« CL 11107044 / 5baf6060648e
cmd/gc: avoid passing unevaluated constant expressions to backends.

Backends do not exactly expect receiving binary operators with
constant operands or use workarounds to move them to
register/stack in order to handle them.

Fixes issue 5841.

R=golang-dev, daniel.morsing, rsc
CC=golang-dev
https://codereview.appspot.com/11107044

Committer: Russ Cox <rsc@golang.org>
»»»

Update issue 5928

[adg, 2013-07-25 23:38:37]

Hello golang-dev@googlegroups.com,

I'd like you to review this change to
https://code.google.com/p/go

[dfc, 2013-07-25 23:43:20]

LGTM. 

On 26/07/2013, at 9:38, adg@golang.org wrote:

> Reviewers: golang-dev1,
> 
> Message:
> Hello golang-dev@googlegroups.com,
> 
> I'd like you to review this change to
> https://code.google.com/p/go
> 
> 
> Description:
> [release-branch.go1.1] cmd/gc: avoid passing unevaluated constant
> expressions to backends.
> 
> ««« CL 11107044 / 5baf6060648e
> cmd/gc: avoid passing unevaluated constant expressions to backends.
> 
> Backends do not exactly expect receiving binary operators with
> constant operands or use workarounds to move them to
> register/stack in order to handle them.
> 
> Fixes issue 5841.
> 
> R=golang-dev, daniel.morsing, rsc
> CC=golang-dev
> https://codereview.appspot.com/11107044
> 
> Committer: Russ Cox <rsc@golang.org>
> »»»
> 
> Update issue 5928
> 
> Please review this at https://codereview.appspot.com/11879044/
> 
> Affected files:
>  M src/cmd/gc/walk.c
>  A test/fixedbugs/issue5841.go
> 
> 
> Index: src/cmd/gc/walk.c
> ===================================================================
> --- a/src/cmd/gc/walk.c
> +++ b/src/cmd/gc/walk.c
> @@ -1338,6 +1338,13 @@
>    fatal("missing switch %O", n->op);
> 
> ret:
> +    // Expressions that are constant at run time but not
> +    // considered const by the language spec are not turned into
> +    // constants until walk. For example, if n is y%1 == 0, the
> +    // walk of y%1 may have replaced it by 0.
> +    // Check whether n with its updated args is itself now a constant.
> +    evconst(n);
> +
>    ullmancalc(n);
> 
>    if(debug['w'] && n != N)
> Index: test/fixedbugs/issue5841.go
> ===================================================================
> new file mode 100644
> --- /dev/null
> +++ b/test/fixedbugs/issue5841.go
> @@ -0,0 +1,16 @@
> +// build
> +
> +// Copyright 2013 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.
> +
> +// Issue 5841: 8g produces invalid CMPL $0, $0.
> +// Similar to issue 5002, used to fail at link time.
> +
> +package main
> +
> +func main() {
> +    var y int
> +    if y%1 == 0 {
> +    }
> +}
> 
> 
> -- 
> 
> ---You received this message because you are subscribed to the Google Groups
"golang-dev" group.
> To unsubscribe from this group and stop receiving emails from it, send an
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> 
> 

[adg, 2013-07-26 00:04:41]

*** Submitted as https://code.google.com/p/go/source/detail?r=8c514a33ecd0 ***

[release-branch.go1.1] cmd/gc: avoid passing unevaluated constant expressions to
backends.

««« CL 11107044 / 5baf6060648e
cmd/gc: avoid passing unevaluated constant expressions to backends.

Backends do not exactly expect receiving binary operators with
constant operands or use workarounds to move them to
register/stack in order to handle them.

Fixes issue 5841.

R=golang-dev, daniel.morsing, rsc
CC=golang-dev
https://codereview.appspot.com/11107044

Committer: Russ Cox <rsc@golang.org>
»»»

Update issue 5928

R=golang-dev, dave
CC=golang-dev
https://codereview.appspot.com/11879044

[dfc, 2013-07-26 07:43:13]

For some reason all the builders decided not to build this revision. Did it
commit cleanly ?