python27 @2.7.2_4 subports fail to build when compiler path changes

[benoit.triquet@…]

python27 records the compiler path when built and that path is later used to build modules such as py27-tkinter, which fails if the compiler changes locations such as with the transition from Xcode 4.1 to Xcode 4.3

A work-around is to force a rebuild of python without dependent rebuilds:

port -n upgrade --force python27

Suggestions of solutions: 1) have the perl and python portgroups check that the compiler hardcoded

into the interpreter is still available, and tell the user to rebuild as necessary

2) make perl/python/etc modules build using ${configure.compiler}

instead of the compiler used by the interpreter.

(1) is more a work-around than a fix (i don't know the rules of macports but i believe interactions shall be forbidden) but should be otherwise harmless. (2) may fail to guarantee that the newly found compiler is link- and abi- compatible with the previous one, so it's not clear that this solution is fine. Then again, it's not clear that a new compiler found at the recorded solution, as would be silently accepted in the current implementation of python27, is fine either.

PS: thanks to Dan Ports for identifying my problem and providing the above work-around and suggestions. Dan says that other python versions may be affected as well as perl5, apr and postgresql.

[jmroot (Joshua Root)]

Note that any port affected by this is not using the unified portgroup, so doing that would be the preferred fix. We've also switched the default from paths in /Developer/usr/bin to ones in /usr/bin, which should be a lot less likely to move in future.

[benoit.triquet@…]

I confirm a similar occurrence with a perl dependent, forcing the rebuild of perl5.12 + cleaning the dependent allowed the dependent to build.

[jmroot (Joshua Root)]

2.0.4 uses compilers from /usr/bin if at all possible, and python27 has just been updated.