x86_64-signal.h (MAKE_THROW_FRAME): Mark sigcontext on stack volatile to prevent optimization from removing it.

2003-06-03  Andrew Haley  <aph@redhat.com>

        * include/x86_64-signal.h (MAKE_THROW_FRAME): Mark sigcontext on
        stack volatile to prevent optimization from removing it.

From-SVN: r67379