why emitting unwind labels?

[Jack Howarth]

   Interestingly, on darwin, it appears that the trigger for the generation
of the duplicate .eh symbols is not -freorder-blocks-and-partition but the
additional use of -fprofile-use -D_PROFILE_USE. When I drop the profiling
from gcc.dg/tree-prof/bb-reorg.c and gcc.dg/tree-prof/pr34999.c, they compile
without error. I guess I need to add flag_profile_use to the cases where
-freorder-blocks-and-partition should be disabled when generating eh labels
on darwin.
                Jack