This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: V3 PATCH: __cxa_guard_acquire
- From: Richard Henderson <rth at redhat dot com>
- To: Mark Mitchell <mark at codesourcery dot com>
- Cc: "gcc-patches at gcc dot gnu dot org" <gcc-patches at gcc dot gnu dot org>, "libstdc++ at gcc dot gnu dot org" <libstdc++ at gcc dot gnu dot org>
- Date: Tue, 26 Nov 2002 00:03:20 -0800
- Subject: Re: V3 PATCH: __cxa_guard_acquire
- References: <20021126012006.GB25134@redhat.com> <5790000.1038284698@warlock.codesourcery.com>
On Mon, Nov 25, 2002 at 08:24:58PM -0800, Mark Mitchell wrote:
> Yes, it really wants a 64-bit type. It wants 8 bits for a flag, and
> 7 other bytes for use as appropriate on the particular OS; the idea
> is that you might hide a mutex in those other 7 bytes. You wouldn't
> want to shrink this to 4 bytes on a 32-bit architecture; you want
> 4 bytes that you can use as the mutex.
If you want to be sure of a mutex, you have to do more.
PA-RISC, for instance, requires that it's mutexes be
16 *byte* aligned.
r~