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Re: -Wall incorrectly complains about scanf with %a
On 26-mei-04, at 2:04, Eljay Love-Jensen wrote:
Hi Paul,
I agree with you that the compiler's complaint is incorrect.
"%a" isn't a valid format specifier.
But it is. It is equivalent to %e, %f, or %g.
Well, this is "new" in C99... ("new" as a five year old
standard sure can't be called new anymore).
"%as" is a valid format specifier, and it takes an address of an
uninitialized char pointer, which will be set to a malloc'd value
sufficient to hold the character array.
Also note (http://www.rt.com/man/scanf.3.html), the "a" modifier is
not part of ANSI C. It's a GNU libc extension.
So glibc needs to change, as %a is taken by ISO C now.
Good catch! File a bug.
Against glibc, please ;-)
[And maybe GCC should warn if operating in some compatibility mode].
Segher