code review 66930044: cmd/gc: fix walkcompare bugs.

cmd/gc: fix walkcompare bugs.

Revision c0e0467635ec (cmd/gc: return canonical Node* from temp)
exposed original nodes of temporaries, allowing callers to mutate
their types.

In walkcompare a temporary could be typed as ideal because of
this. Additionnally, assignment of a comparison result to
a custom boolean type was broken.

Fixes issue 7366.

[remyoudompheng, 2014-02-23 22:37:08]

Hello rsc@golang.org, iant@golang.org, khr@golang.org (cc:
golang-codereviews@googlegroups.com),

I'd like you to review this change to
https://go.googlecode.com/hg/

[rsc, 2014-02-24 16:30:22]

LGTM

thank you very much

[remyoudompheng, 2014-02-24 18:52:09]

*** Submitted as https://code.google.com/p/go/source/detail?r=3ae4607a43ff ***

cmd/gc: fix walkcompare bugs.

Revision c0e0467635ec (cmd/gc: return canonical Node* from temp)
exposed original nodes of temporaries, allowing callers to mutate
their types.

In walkcompare a temporary could be typed as ideal because of
this. Additionnally, assignment of a comparison result to
a custom boolean type was broken.

Fixes issue 7366.

LGTM=rsc
R=rsc, iant, khr
CC=golang-codereviews
https://codereview.appspot.com/66930044

[gobot, 2014-02-24 19:42:16]

This CL appears to have broken the openbsd-386-rootbsd builder.