[libunwind] Build with -funwind-tables

This adds the -funwind-tables flag when compiling libunwind. This allows
unwinding past, eg. _Unwind_RaiseException.
The upstream cmake build adds it when it is supported, and generation of
unwind tables is already done for all the libunwind C++ code since
it compiles with exceptions enabled.

Also pass -fexceptions to the C code on Fuchsia only to work around
https://bugs.llvm.org/show_bug.cgi?id=45875.

Bug: 1078588
Change-Id: Id821f143c12e7e1e376eea534be52c6cd8504465
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2218273
Commit-Queue: Nico Weber <thakis@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#774598}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: d20e971be2ed23cb82ac7b32bc102fd5412f8241
1 file changed