-floop-flatten and PR 52307

[Richard Guenther]

On Sun, Feb 26, 2012 at 1:32 PM, Thomas Koenig <tkoenig@netcologne.de> wrote:
> Hello world,
>
> -floop-flatten breaks Lapack, which uses quite a common technique; see
>
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52307
>
> This is not a regression as far as I can determine, but the bug is
> severe enough that I would consider removing the option for the 4.7
> release.
>
> Opinions?

Why remove it?  Just document it is experimental.  It's not turned on by
default at any optimization level - and it even lacks a cost model, so is
not really useful.

Richard.

>        Thomas