Re: gcc fixed size char array initialization bug - known?

[Guennadi Liakhovetski <g.liakhovetski@gmx.de>]

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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