Pull in r315334 from upstream lld trunk (by Rafael Espindola):
Don't create a dummy __tls_get_addr. We just don't need one with the current setup. We only error on undefined references that are used by some relocation. If we managed to relax all uses of __tls_get_addr, no relocation uses it and we don't produce an error. This is less code and fixes the case were we fail to relax. Before we would produce a broken output, but now we produce an error.
Pull in r320390 from upstream lld trunk (by Rafael Espindola):
Create reserved symbols early so they can be versioned. This fixes pr35570. We were creating these symbols after parsing version scripts, so they could not be versioned. We cannot move the version script parsing later because we need it for lto. One option is to move both addReservedSymbols and createSyntheticSections earlier. The disadvantage is that some sections created by createSyntheticSections replace other input sections. For example, gdb index replaces .debug_gnu_pubnames, so it wants to run after gc sections so that it can set S->Live to false. What this patch does instead is to move just the ElfHeader creation early.
Pull in r320412 from upstream lld trunk (by Rafael Espindola):
Handle symbols pointing to output sections. Now that gc sections runs after linker defined symbols are added it can see symbols that point to an OutputSection. Should fix a bot failure.
Pull in r320431 from upstream lld trunk (by Peter Collingbourne):
ELF: Do not follow relocation edges to output sections during GC. This fixes an assertion error introduced by r320390. Differential Revision: https://reviews.llvm.org/D41095
Together these fix handling of reserved symbols, in particular _end,
which is needed to make brk(2) and sbrk(2) work correctly. This
unbreaks the emacs ports on amd64, and also appears to unbreak most of
world on i386.
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D13466