tree 6a0ab6df0be6b560142e8d9b0a71e839a947f339
parent 0fefcf71a7fe4e24cfcedfd15ab4baa932e3df43
author Shoaib Meenai <smeenai@fb.com> 1538610791 +0000
committer Shoaib Meenai <smeenai@fb.com> 1538610791 +0000

[ELF] Fix crash on invalid undefined local symbols

r320770 made LLD handle invalid DSOs where local symbols were found in
the global part of the symbol table. Unfortunately, it didn't handle the
case where those local symbols were also undefined, and r326242 exposed
an assertion failure in that case. Just warn on that case instead of
crashing, by moving the local binding check before the undefined symbol
addition.

The input file for the test is crafted by hand, since I don't know of
any tool that would produce such a broken DSO. I also don't understand
what it even means for a symbol to be undefined but have STB_LOCAL
binding - I don't think that combination makes any sense - but we have
found broken DSOs of this nature that we were linking against. I've
included detailed instructions on how to produce the DSO in the test.

Differential Revision: https://reviews.llvm.org/D52815

git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@343745 91177308-0d34-0410-b5e6-96231b3b80d8