int to bool performance warning?

This is a discussion on int to bool performance warning? within the C Programming forums, part of the General Programming Boards category; In MSVC the following line gives me a performance warning c4800, I thought casting isdigit to a bool would 'fix' ...

  1. #1
    Registered User Bajanine's Avatar
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    int to bool performance warning?

    In MSVC the following line gives me a performance warning c4800, I thought casting isdigit to a bool would 'fix' it but I still receive the warning.

    Code:
    digit = isdigit(temp[count]);
    Using Bloodshed I don't get the warning using: -Wall -std=c99.

    What do I need to do to get rid of this warning in MSVC 2003?
    Favorite Quote:

    >For that reason someone invented C++.
    BLASPHEMY! Begone from my C board, you foul lover of objects, before the gods of C cast you into the void as punishment for your weakness! There is no penance for saying such things in my presence. You are henceforth excommunicated. Never return to this house, filthy heretic!



  2. #2
    and the hat of wrongness Salem's Avatar
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    RETURN VALUE
    The values returned are nonzero if the character c falls into the tested class, and a
    zero value if not.

    So perhaps
    Code:
    digit = isdigit(temp[count]) != 0;
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.
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  3. #3
    Registered User Bajanine's Avatar
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    Thanks Salem I get it now.
    Favorite Quote:

    >For that reason someone invented C++.
    BLASPHEMY! Begone from my C board, you foul lover of objects, before the gods of C cast you into the void as punishment for your weakness! There is no penance for saying such things in my presence. You are henceforth excommunicated. Never return to this house, filthy heretic!



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