K 10
svn:author
V 6
emaste
K 8
svn:date
V 27
2016-01-09T00:42:07.479229Z
K 7
svn:log
V 501
Support use of LLVM's libunwind for exception unwinding

It is built in libgcc_s.so and libgcc_eh.a to simplify transition.

It is enabled by default on arm64 (where we previously had no other
unwinder) and may be enabled for testing on other platforms by setting
WITH_LLVM_LIBUNWIND in src.conf(5).

Also add compiler-rt's __gcc_personality_v0 implementation for use with
the LLVM unwinder.

Relnotes:	Yes
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D4787

END