Slashdot Mirror

← Back to Stories (view on slashdot.org)

GCC Gets PCH Support And New Parser

Posted by timothy on from the it's-warm-blooded dept.

Screaming Lunatic writes "GCC will finally get precompiled header support which should help with faster compile times. GCC will also be fitted with a new recursive descent parser that fixes more than 100 bugs in GCC. I'm not sure how they decomposed C++ into a context free grammar so that it could be parsed using recursive descent."

3 of 83 comments (clear)

  1. Re:Why the extra step? by PD · · Score: 5, Insightful

    No, object files are built one at a time with a makefile. The correlation would be if we just typed "gcc" in a directory and the compiler built every cpp file into an object. What if I didn't want a file compiled? What if that file was supposed to be copied into a directory after it was built with another tool? In that case, gcc would be doing the wrong thing by building every .o automatically.

    A makefile lets me control the building of each and every .o file myself, allowing for all sorts of things that I might want to do.

    Precompiled headers should work the same way, or they won't be as flexible as the .h files.

    --
    If tits were wings it'd be flying around.
  2. Well done GCC, but.... by peterpi · · Score: 4, Insightful

    ... in my experience, good use of forward declarations (to avoid unrequired chains of #include), combined with simply putting less in each .c file is a lot more effective than adding the complication of precompiled headers into your build process.

    1. Re:Well done GCC, but.... by sohp · · Score: 4, Insightful

      That's exactly the sort of rule of thumb that John S. Lakos talks about in his terrific book, Large-Scale C++ Software Design (ISBN: 0201633620). Basically, pre-compiled headers are for developers who are too lazy or inexperienced to manage inter-module dependencies efficiently.