[PATCH] libcsupport: Workaround for GCC 5.1 and later

[Chris Johns]

On 14/07/2015 4:20 am, Joel Sherrill wrote:
> 
> 
> On 7/13/2015 1:06 PM, Sebastian Huber wrote:
>> Yes, this option sounded like the right way to fix it, but...
>>
>> https://gcc.gnu.org/ml/gcc-help/2015-03/msg00093.html
>> https://gcc.gnu.org/ml/gcc-help/2015-03/msg00094.html
> 
> Ouch! That is a big red flashing sign which says stay away!
> 
> And to Gedare's point of raising this as a PR, it is just
> an optimization side-effect more than bug.
> 
> I wonder if this could impact any code in newlib? It should
> have the same issue with the default calloc(). And maybe
> some other routines like the string and mem* ones?
> 

For the record can someone please explain why 'calloc' broke with gcc 5
on ARM in the first place ?

What is the code construct in that specific function [1] that is causing
the issue in the first place ? It seems a common type of idiom and I am
sure it must exist in user code.

Chris

[1] https://git.rtems.org/rtems/tree/cpukit/libcsupport/src/calloc.c