RFC: Stricter semantics for renaming pragmas

[Ian Lance Taylor]

Joe Buck <Joe.Buck@synopsys.COM> writes:

> On Tue, May 18, 2004 at 07:54:08PM -0700, Zack Weinberg wrote:
> > We currently have three ways of changing the object-file name of a
> > variable or function.  They are __asm__("foo") tacked on the end of
> > the declaration; #pragma redefine_extname; #pragma extern_prefix.
> 
> Who is using this feature now?  (That is, which well-known programs? glibc?).
> Which of the three ways is most commonly used?
> 
> That matters because any simplifications that are made should try to break
> as little as possible.

#pragma redefine_extname appears in Solaris system headers.  Support
for it is required to compile programs on Solaris.  For example, see
    http://gcc.gnu.org/ml/gcc-patches/2001-11/msg01966.html
although a different patch was later adopted.

I presume from the documentation that #pragma extern_prefix appears in
Tru64 system headers, but I don't know that from direct observation.

I hope that neither #pragma is used anywhere else.

__asm__ is of course an old extension used by many people, including
glibc.

Ian