How do I set SIG_ATOMIC_TYPE to a variant of a C-type?

[Joseph S. Myers]

On Tue, 15 May 2012, Hans-Peter Nilsson wrote:

> How do I accomplish setting SIG_ATOMIC_TYPE as above?

GCC only needs to know this type for the purposes of defining limits for 
stdint.h.  Unless your signal.h does

typedef __SIG_ATOMIC_TYPE__ sig_atomic_t;

this should only affect the testcases gcc.dg/c99-stdint-[56].c, not actual 
user code.  And as you have discovered, there are rules for these type 
strings documented in tm.texi under SIZE_TYPE; to use some other variant 
you'll need to find and eliminate all the dependencies on whatever rule 
you wish to change.

Logically these macros should be hooks returning enumeration values from a 
defined set of possible types, not strings at all.  See past discussions 
with Joern, e.g. <http://gcc.gnu.org/ml/gcc-patches/2010-11/msg02900.html> 
and <http://gcc.gnu.org/ml/gcc-patches/2010-12/msg00964.html>.

-- 
Joseph S. Myers
joseph@codesourcery.com