Arch Linux User Repository

I highly recommend building this package in a clean chroot. This avoids the use of a AUR helper, which sometimes uses /tmp as the stating directory, which often gets filled completely by gcc's build process.

It also provides a clean environment, which minimizes interactions between your current environment and gcc's build process.

@yeahren just checked - download is fine. Maybe your ISP blocking some sites?

ERROR: Failure while downloading http://isl.gforge.inria.fr/isl-0.18.tar.bz2

and https://gcc.gnu.org/pub/gcc/infrastructure/isl-0.18.tar.bz2 is fine

Should be fixed now

@dviktor, sorry for the late response. I don't really use gcc6 anymore and unfortunately I don't have the time to look at this. I've transferred maintainership to you. Good luck!

Why libgcc_s.so.1 is not in the /usr/lib/gcc/x86_64-pc-linux-gnu/6.5.0?

Checking with ldd says that I'm still linked to the /usr/lib/libgcc_s.so.1 while needed library is in /usr/lib/gcc/x86_64-pc-linux-gnu/lib

Just compared with community gcc7-libs package - they are moving libgcc_s.so libraries to the proper place by hand

@berquist you have two options:

1) run export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/lib/gcc/x86_64-pc-linux-gnu/6.5.0 before you execute the program

2) create /etc/ld.so.conf.d/gcc5.conf with the following contents:

/usr/lib/gcc/x86_64-pc-linux-gnu/6.5.0

And then run ldconfig as root, it should be fixed.

Maybe I should add this file to the package but I'm not sure if it may have unintended side-effects.

Something is wrong with the library path for gfortran. Try compiling this program:

      PROGRAM MAIN
      WRITE(*,*) 'Here is some text'
      END

gfortran-6 main.F

$ ldd a.out
        linux-vdso.so.1 (0x00007fff153be000)
        libgfortran.so.3 => not found
        libm.so.6 => /usr/lib/libm.so.6 (0x00007f707c647000)
        libgcc_s.so.1 => /usr/lib/libgcc_s.so.1 (0x00007f707c62d000)
        libquadmath.so.0 => /usr/lib/libquadmath.so.0 (0x00007f707c5ea000)
        libc.so.6 => /usr/lib/libc.so.6 (0x00007f707c426000)
        /lib64/ld-linux-x86-64.so.2 => /usr/lib64/ld-linux-x86-64.so.2 (0x00007f707c7fd000)

I spent some time getting gcc6 to build gcj with an complete java 5 environment. A PKGBUILD for a 6.5.0-2 based on 6.5.0-1 is here:

https://gist.github.com/bbidulock/6968e85305fe4009cdc5ad5f037cae09

That PKGBUILD builds without issue in a clean chroot for both x86_64 and i686 architectures.

Would it be possible to review these changes and incorporate them into gcc6?

@lonaowna

Thanks a lot, unfortunately I have tried these steps and installed different versions of compilers (4.9, 4.9.3, 5, 6.4, 7 etc.) However, MATLAB did not even accept gcc6.4 (from gcc63-multilib). I have edited "mex_C++_glnxa64.xml" and the output is below. Lastly, I also tried to compile 6.3.0 from source but it gives an error called "error 2". Therefore, I am a bit out of options. Is there a way to make this library to give 6.3 version when it requested -dumpversion :)

mex -setup C++ -v

Verbose mode is on.

... Looking for compiler 'g++' ...

... Executing command 'which g++' ...Yes ('/bin/g++').

... Executing command 'g++ -print-file-name=libstdc++.so' ...Yes ('/usr/lib/libstdc++.so').

... Executing command 'g++ -dumpversion' ...Yes ('8.2.1').

... Executing command 'which g++' ...Yes ('/bin/g++').

... Looking for folder '' ...No.

Did not find installed compiler 'g++'.

... Looking for compiler 'gcc-6' ...

... Executing command 'which gcc-6' ...Yes ('/bin/gcc-6').

... Executing command 'gcc-6 -print-file-name=libstdc++.so' ...Yes ('/usr/lib/gcc/x86_64-pc-linux-gnu/6.5.0/libstdc++.so').

... Executing command 'gcc-6 -dumpversion' ...Yes ('6.5.0').

... Executing command 'which gcc-6' ...Yes ('/bin/gcc-6').

... Looking for folder '' ...No.

Did not find installed compiler 'gcc-6'.

... Looking for compiler 'g++-6' ...

... Executing command 'which g++-6' ...Yes ('/bin/g++-6').

... Executing command 'g++-6 -print-file-name=libstdc++.so' ...Yes ('/usr/lib/gcc/x86_64-pc-linux-gnu/6.5.0/libstdc++.so').

... Executing command 'g++-6 -dumpversion' ...Yes ('6.5.0').

... Executing command 'which g++-6' ...Yes ('/bin/g++-6').

... Looking for folder '' ...No.

Did not find installed compiler 'g++-6'.

Error using mex

No supported compiler was found. For options, visit https://www.mathworks.com/support/compilers.

@ElektrikAkar no, this is 6.5.0, which should be compatible with all 6.x.x releases as it just adds some bugfixes.

Did you try editing mex_C_glnxa64.xml as described here? (for this package use Location="/usr/bin/gcc-6")

Edit: depending on your MATLAB version maybe follow this instead. (use CC='gcc-6' and CXX='g++-6')