[arch-general] [arch-dev-public] Test repository with gcc7

[Hao Zhang]

On Monday, May 15, 2017 5:33:05 AM MDT Bartłomiej Piotrowski wrote:
> On 2017-05-12 03:22, Hao Zhang via arch-general wrote:
> > On 2017-05-10 20:19, Bartłomiej Piotrowski wrote:
> >> I found some time today to make a test build of the latest GCC. I tested
> >> some "simple" projects like nginx and libtorrent-rasterbar and they do
> >> build, while MariaDB fails on linking for me.
> >> 
> >> Let me know if you encounter any problems, I'd rather not break too much
> >> by pushing it to repos.
> >> 
> >> [gcc7]
> >> SigLevel = Required
> >> Server = https://pkgbuild.com/~bpiotrowski/gcc7
> >> 
> >> No i686, embrace the future!
> >> 
> >> Bartłomiej
> > 
> > Hi Bartłomiej,
> > 
> > I found MariaDB fails on linking because /usr/bin/gcc-ar segfaults
> > whenever
> > it runs with absolute path. I have filed an upstream bug report:
> > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80717
> > 
> > Hao
> 
> Thanks for spending time on it and reporting upstream! Really appreciate it.
> 
> I also heard that retroarch fails, but I couldn't reproduce it locally.
> I will push new gcc to [testing] this week.
> 
> Bartłomiej
Hi Bartłomiej,

Thank you very much! I also tried building retroarch and have no problem 
building it with GCC 7. Now we found the reason why MariaDB fails to build, 
there are two ways of fixing it and I have verified both methods work:
1) patch gcc to remove line 197-203 from gcc-ar.c (these lines are not present 
in gcc 6.3.1)
2) make a symlink of the files ar, nm and ranlib in /usr/local/bin.

A more serious problem with GCC 7 is the ABI changes in libgfortran (major 
version bumped from 3 to 4). Many packages depending on libgfortran such as 
python-numpy needs to be recompiled. Some binary packages such as MATLAB just 
refuse to run with libgfortran7 and these binary packages cannot be 
recompiled...

Hao