Make ElfCache follow .gnu_debuglink
authorMark Williams <mwilliams@fb.com>
Wed, 14 Sep 2016 22:48:52 +0000 (15:48 -0700)
committerFacebook Github Bot 2 <facebook-github-bot-2-bot@fb.com>
Wed, 14 Sep 2016 22:53:38 +0000 (15:53 -0700)
commit3272dfdbe243e0ac02acca1dd82bc391d1da079a
tree6e23f64f6caad2a9c87a962dd2c57a94e71025d8
parent9f838616d97b3d2b62a74b7d80f38f32e5d316df
Make ElfCache follow .gnu_debuglink

Summary:
If you split out debug info into a separate file, folly::Symbolizer
didn't find it, and failed to include file and line number info in
backtraces.

This adds a new open mode which follows the .gnu_debuginfo link, and
uses it from ElfCache and SignalSafeElfCache.

Reviewed By: meyering, luciang

Differential Revision: D3852311

fbshipit-source-id: fec9e57378ae59fa1b82d41a163bb9cfcf9ca23c
folly/experimental/symbolizer/Elf.cpp
folly/experimental/symbolizer/Elf.h
folly/experimental/symbolizer/ElfCache.cpp
folly/experimental/symbolizer/test/gnu_debuglink_test.sh [new file with mode: 0755]