python config with ccache in CC causes scipy build failure

[dmmonarres@…]

py26-scipy fails to build with a linking error. Fails when trying to link using gcc-4.2.

/opt/local/bin/g++-mp-4.3 /usr/bin/gcc-4.2 -L/opt/local/lib -bundle -undefined dynamic_lookup build/temp.macosx-10.6-x86_64-2.6/scipy/interpolate/src/_interpolate.o -Lbuild/temp.macosx-10.6-x86_64-2.6 -o build/lib.macosx-10.6-x86_64-2.6/scipy/interpolate/_interpolate.so
ld: in /usr/bin/gcc-4.2, can't link with a main executable
collect2: ld returned 1 exit status
ld: in /usr/bin/gcc-4.2, can't link with a main executable
collect2: ld returned 1 exit status

Attached is the full output of port -d install py26-scipy

[skymoo (Adam Mercer)]

You seem to be using ccache, have you the configureccache option set in ${prefix}/etc/macports/macports.conf? If so try disabling it and try again, after cleaning.

[bgrant@…]

Full output of: sudo port clean --dist py26-scipy; sudo port -d install py26-scipy

[bgrant@…]

Replying to ram@…:

You seem to be using ccache, have you the configureccache option set in ${prefix}/etc/macports/macports.conf? If so try disabling it and try again, after cleaning.

I think I'm having the same problem. I also had ccache enabled initially, but I've disabled it, and I attached the log of cleaning the port and reinstalling.

[jmroot (Joshua Root)]

Replying to bgrant@…:

I think I'm having the same problem. I also had ccache enabled initially, but I've disabled it, and I attached the log of cleaning the port and reinstalling.

This log shows that ccache is still being used. The configure.ccache setting should not actually make any difference to scipy's portfile. I'm guessing the bad compiler value is being picked up from the python config, which means you would have to rebuild python26 with ccache disabled.

[dmmonarres@…]

That is exactly what we found. Python will build modules with the same compiler that itself was built with. I had to rebuild python2.6 with ccache disabled and the problem went away.

Replying to jmr@…:

Replying to bgrant@…:

I think I'm having the same problem. I also had ccache enabled initially, but I've disabled it, and I attached the log of cleaning the port and reinstalling.

This log shows that ccache is stil being used. The configure.ccache setting should not actually make any difference to scipy's portfile. I'm guessing the bad compiler value is being picked up from the python config, which means you would have to rebuild python26 with ccache disabled.

[blb@…]

python26 port now set to not use ccache in r68165. I would have kept it building with ccache but stripping it from python's config/Makefile but it looks like using ccache also causes python's configure to not want to use -fwrapv, which is apparently important according to ​python issue 1608.

CC'ing 2.7 and 3.1 maintainers as they probably also need to disable.

[blb@…]

Confirmed that 2.7 and 3.1 both miss -fwrapv with ccache enabled, so it's disabled there as well in r68616.