[PATCH], Add configuration checks to PowerPC --with-long-double-format=ieee

[Segher Boessenkool]

On Fri, Jul 06, 2018 at 09:38:02AM -0400, Michael Meissner wrote:
> On Fri, Jul 06, 2018 at 06:38:55AM -0500, Segher Boessenkool wrote:
> > On Fri, Jul 06, 2018 at 01:51:37AM -0400, Michael Meissner wrote:
> > >  case "$target:$with_long_double_format" in
> > 
> > > -  xpowerpc64*-*-linux*:*)
> > 
> > So this case could never happen.  The changelog should mention it fixes
> > that bug (and having it as a separate patch is much preferred!)
> 
> I assume what happened is I accidently added the 'x' to the working copy after
> submitting the patch, but before committing it and I didn't notice it.  Since
> it is in configuration support, it isn't part of the test sutie, and it wasn't
> noticed.
> 
> I can add a line to the ChangeLog if desired.
> 
> > Other than this thing, the original code was easier to read.  What does
> > this part of the patch improve?
> 
> You complained that you were getting errors when using the system glibc (based
> on 2.27 on an Ubuntu system) and using --with-long-double-format=ieee (where it
> would die in the middle of building libstdc++-v3).

No, _this part_ of the patch.  The part that doesn't change behaviour (but
see above):

	* configure.ac (powerpc64*-*-linux*): Combine big and little
	endian checks for the long double format.

I asked Tulio to comment on if this is a good way to detect usable glibc
versions for default ieee long double.  I haven't reviewed that part of
your patch yet.


Segher