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    SubjectGCC still keeps empty loops? (was: [patch 4/21] fix ARCH_HAS_PREFETCH)
    Linus Torvalds wrote:
    > I thought that special case was removed long ago, because it is untenable
    > in C++ etc (where such empty loops happen due to various abstraction
    > issues, and not optimizing them away is just silly).
    > But testing shows that you're right at least for 2.95 and 2.96. Argh

    Unbelievably, 3.1 doesn't remove empty loops either.
    I think there's a case for a compiler flag, `-fremove-empty-loops'.

    Empty loop delays aren't portable acrosss compilers in general. If you
    _really_ want an empty loop that must always work with GCC, it's easy
    enough to write:

    for (i = 0; i < 100000; i++)
    __asm__ __volatile__ ("");

    -- Jamie
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      Last update: 2005-03-22 13:27    [W:0.034 / U:13.644 seconds]
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