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SubjectRe: gcc fixed size char array initialization bug - known?
On Thu, 2 Aug 2007, Andi Kleen wrote:

> Guennadi Liakhovetski <g.liakhovetski@gmx.de> writes:
>
> > char c[4] = "0123";
> > and - a wonder - no warning.
>
> It's required by the C standard.
>
> 6.7.8.14 of C99:
> ``
> An array of character type may be initialized by a character string literal, optionally
> enclosed in braces. Successive characters of the character string literal (including the
> terminating null character if there is room or if the array is of unknown size) initialize the
> elements of the array.
> ''
>
> Note the "if there is room".
>
> I believe the rationale is that it still allows to conveniently initialize
> non zero terminated strings.

Right, I accept that it will compile, but I don't understand why "01234"
produces a warning and "0123" doesn't? Don't think C99 says anything about
that. And, AFAIU, using structs with fixed-size char array we more or less
rely on the compiler warning us if anyone initializes it with too long a
string.
Also interesting, that with

char c[4] = "012345";

the compiler warns, but actually allocates a 6-byte long array...

Thanks
Guennadi
---
Guennadi Liakhovetski
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