[committed] restore a test inadvertently removed in r278621 (PR 92683))

[Martin Sebor]

In r278621 I accidentally removed a test that prevented
an optimization from taking place when it wasn't supposed to,
causing test failures in Jeff's mass rebuilds of downstream
packages (e.g., snapd).  In r278742 I committed the attached
patch, restoring the test.

Martin
-------------- next part --------------
A non-text attachment was scrubbed...
Name: gcc-92683.diff
Type: text/x-patch
Size: 8175 bytes
Desc: not available
URL: <http://gcc.gnu.org/pipermail/gcc-patches/attachments/20191127/73caf613/attachment.bin>