Re: Static variables

2013-07-08 Thread Franco Fichtner
Hi Maxime,

On Jul 8, 2013, at 10:40 AM, Maxime Villard rusty...@gmx.fr wrote:

 the static variables are not initialized?

Static variables are always zeroed when not specified otherwise.


Regards,
Franco



Re: Static variables

2013-07-08 Thread Maxime Villard
Le 08/07/2013 11:00, Franco Fichtner a écrit :
 Hi Maxime,
 
 On Jul 8, 2013, at 10:40 AM, Maxime Villard rusty...@gmx.fr wrote:
 
 the static variables are not initialized?
 
 Static variables are always zeroed when not specified otherwise.
 
 
 Regards,
 Franco
 
 

Ah, yes. I didn't know.



Re: Static variables

2013-07-08 Thread Matthew Dempsky
On Mon, Jul 8, 2013 at 2:06 AM, Maxime Villard rusty...@gmx.fr wrote:
 Ah, yes. I didn't know.

For what it's worth, this is specified in C99 §6.7.8 (Initializaton)
paragraph 10:

If an object that has static storage duration is not initialized
explicitly, then:
— if it has pointer type, it is initialized to a null pointer;
— if it has arithmetic type, it is initialized to (positive or unsigned) zero;
— if it is an aggregate, every member is initialized (recursively)
according to these rules;
— if it is a union, the first named member is initialized (recursively)
according to these rules.

On OpenBSD (and most, if not all, ELF platforms), this is implemented
by assigning these objects into the .bss section, which is initialized
to all zero bytes at program startup, taking advantage of the fact
that all of our platforms represent null pointers and zero values as
sequences of zero bytes.