Re: Change in strncmp, at least on PowerPC

[Andreas Schwab]

Bob Schmertz <address@hidden> writes:

> The problem is this: if strncmp is called with a null pointer for at
> least one of the strings, and n is supplied as 0, it segfaults.

Don't do that then.

7.21.1 String function conventions

2.  Where an argument declared as size_t n specifies the length of the
    array for a function, n can have the value zero on a call to that
    function. Unless explicitly stated otherwise in the description of a
    particular function in this subclause, pointer arguments on such a
    call shall still have valid values, as described in 7.1.4.

7.1.4 Use of library functions

1.  ... If an argument to a function has an invalid value (such as a value
    outside the domain of the function, or a pointer outside the address
    space of the program, or a null pointer, or a pointer to
    non-modifiable storage when the corresponding parameter is not
    const-qualified) or a type (after promotion) not expected by a
    function with variable number of arguments, the behavior is undefined.

> This difference has broken zsh on the PPC platform.

zsh is broken.

Andreas.

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Andreas Schwab, SuSE Labs, address@hidden
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