Require GCC 5 or later to build glibc (bug 23993)

[Adhemerval Zanella]

On 18/12/2018 16:45, Florian Weimer wrote:
> * Joseph Myers:
> 
>> 2018-12-18  Joseph Myers  <joseph@codesourcery.com>
>>
>> 	[BZ #23993]
>> 	* configure.ac (libc_cv_compiler_ok): Require GCC 5 or later.
>> 	* configure: Regenerated.
>> 	* manual/install.texi (Tools for Compilation): Update minimum GCC
>> 	version.
>> 	* INSTALL: Regenerated.
> 
> Patch looks okay to me.
> 
> However, can we keep support/ at a GCC 4.9 level for some time?  This
> will simplify backporting to glibc 2.27 and 2.28.  I expect to backport
> regularly to these branches for about a year, maybe longer, particularly
> for glibc 2.28.
> 
> Thanks,
> Florian
> 

Wouldn't be better to focus on change toolchain requirements at the start
of release cycle?