William Stein wrote: > On Wed, Aug 12, 2009 at 7:31 AM, Dr. David > Kirkby<david.kir...@onetel.net> wrote: >> When one types 'make', a configure script is run. That checks for >> various things (not very much currently), but it does check the gcc >> version and the perl version, plus a few other things. >> >> One issue is that if someone starts a build, stops it, then restarts it >> by typing 'make', those checks will not take place a second time. If the >> build environment has changed, then this will not be detected. This >> seems a bit dangerous to me. >> >> Consider the following cenerario >> >> 1) Compiler change. >> * Log in and set CC, CXX and SAGE_FORTRAN to the Sun compilers. >> * The build fails (as it will now). >> * On another day, I type 'make', but this time gcc gets used, as I >> forgot to set CC > > How does rerunning the prereq script address this problem at all? The > only thing it does is make sure that gcc satisfies the prereq, but > doesn't do anything else to ensure that CC is compatibly set, etc. It > seems like you've described a theoretical problem that so far I've > never heard anybody complain about, then a solution that doesn't > really solve the problem.
I suspect you will hit few if any problems when people just use the first gcc in their path. If one attempts a build using other compilers, which is going to happen on Solaris at some point, then I think this can be an issue. Certainly one aim was to check that all compilers are compatible still. I've managed to mess this up myself when trying out various compilers - its easy to set CC, but forget CXX or similiar. >> 2) GCC update >> * Start building Sage >> * It fails, so we decide to update gcc >> * Type make again. Now part of the build is with one version gcc, but >> part with another. > > Likewise, re-running prereq doesn't stop this from happening. The > only thing it does is ensure that the new gcc satisfies the prereq. > Is that your point though? I believe this could be cached, so such an issue be detected. Perhaps this is just more work than any possible benefit might provide. I'll leave it as just checking once that all compilers, perl etc at compatible once. Dave --~--~---------~--~----~------------~-------~--~----~ To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
