GCC-4 compiler bug

Simon 'corecode' Schubert corecode at fs.ei.tum.de
Wed Nov 28 15:24:51 PST 2007

Matthew Dillon wrote:
    I was rather surprised that the compiler barfed on that code.  That code
    was, in fact, explicitly testing for an overflow.  Regardless of what
    C99 says, it would be ultra stupid for any compiler to stray outside of
    the type's width.
Yes, I think it is stupid.  But I don't think that any newer GCC version fixes this.  We'll probably have to change GCC not to include this optimization.  Mind you that this happens only for signed overflows.  Unsigned overflow should still work as we expect.

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