Re: conditional use of __thread

[Gabriel Dos Reis <gdr at integrable-solutions dot net>]

Zack Weinberg <zack@codesourcery.com> writes:

| Arnaud Charlet <charlet@ACT-Europe.FR> writes:
| 
| > In a GNAT C run time file, I'd like to make use of the __thread keyword
| > when it is supported by GCC.
| >
| > So far, I couldn't find a way (macro ?) to know in a run time (non
| > compiler) file whether __thread was supported or not.
| >
| > Is there such a way ?
| 
| Doesn't look like it at present.
| 
| > If not, what would be a reasonable way to add this info ?
| 
| Add something like
| 
|   if (targetm.have_tls)
|     cpp_define (pfile, "__TLS__");
| 
| to c-cppbuiltin.c::c_cpp_builtins; document the new feature in
| cpp.texi (Common Predefined Macros section).
| 
| I'm not sure __TLS__ is the best name for this macro.  Anyone have a
| suggestion?

I would suggest it be put in a GCC name space, say,  __GCC_TLS__

-- Gaby