19991027 ICE compiling x11perf

[Alan Modra]

Hi Richard,
   Got this one last night when attempting another full X11 compile.  You
may already have fixed it, as I see you checked in some more changes last
night.  It's hard to keep up with you ;-)

Compile the attached with -O2

GNU C version 2.96 19991027 (experimental) (i586-linux) compiled by GNU C
version 2.96 19991027 (experimental).
x11perf.c: In function `usage':
x11perf.c:472: Internal compiler error in `verify_local_live_at_start', at
flow.c:2533