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in reply to Where should (or could) a distribution override HARNESS_OPTIONS?

[...] but I have found that gcc doesn't seem to support parallel compiling. If two test scripts cause the C/C++ compiler to be invoked at the same time, we get a test failure. I don't think our chances are strong for getting that fixed.

That sounds really strange. When I run make -C/usr/src/linux -j5, several instances of gcc can run in parallel without trouble. So, what is different in Inline::C and Inline::CPP? (I really don't know. The Inline::* modules are still on my TO DO list.) Trivial question: Does each test have its own set of configuration files, gcc input files, gcc output files, gcc temp files?

Alexander

--
Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

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Re^2: Where should (or could) a distribution override HARNESS_OPTIONS?
by davido (Cardinal) on Nov 22, 2012 at 22:09 UTC

    Thanks for pointing this out.

    You could very easily be right with respect to gcc being allowed to run in parallel. That means we've got another problem. I can't speak for Inline::C's test suite, but I can say that no Inline::CPP test is intentionally reliant on any other test. And to answer your question, Inline::CPP generates within an _Inline directory a new subdirectory for each build's files. Nevertheless, there must be some resource that is getting clobbered, and I should be investigating that instead of looking for a means of preventing parallel testing. More research needed in that area, it seems.

    Let's put the Inline::CPP example aside for a moment then, and let the original question stand without any strong example of a module that fits that infinitesimally small category. :)


    Dave

      Inline::CPP generates within an _Inline directory a new subdirectory for each build's files.

      What is a "build" in this context? I.e. do we have one subdirectory per invokation of a test script, one subdirectory per test script, or one per Inline::CPP version? How are the names of the subdirectories calculated (what are the input parameters for the function that returns the subdirectory name)?

      Idea behind the last question: two test scripts, both use a common module that uses Inline:CPP, subdirectory name depends only on that module. Two gccs fight in the same subdirectory.

      (I should really install some Inline::* modules. But it's 6:30 am and it will be a long day at $work. No time for fun ...)

      Alexander

      --
      Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

        "build" refers to Inline creating a module in _Inline (like h2xs) and making it at use/BEGIN time (perl Makefile.PL/make install), before your program runs, ex

        subsequent runs don't "build"

        unless the c-source changes

        The resulting directory structure

        The _Inline/build directory usually gets cleaned up, but not for notdef.pl

        notdef.pl also NAME's the module, so its name doesn't change, but def.pl doesn't NAME the module, so a name is derived from the filename (def.pl) and the md5 sum of the c-source code

        Now, can two copies of notdef.pl run simultaneously? Lets see

        First cleanup  $ rm -rfv _Inline

        And one copy will trip over the other and die , the other will continue normally

        Now I'm not sure what scenario davido is talking about in the OP, but I hope this helps

        FWIW, def.pl/notdef.pl are derived from XS: returning a 64-bit unsigned int?/Re: Inline::C with multiple *.c