RFA: patch to solve PR37535

[David Edelsohn]

Vlad,

This patch breaks bootstrap on PowerPC.  Both my nightly AIX 5.3 and Janis's
nightly RHEL3 bootstrap failed.  The failure is configuring stage 2 libgcc: the
stage 2 xgcc crashes in an alloca call when trying to compile any file.

Was this patch tested on any architecture other than x86?  A patch affecting
clobber behavior deserves more testing.

Thanks, David