Clang r317305 is the first bad revision.

Backtrace with symbols:

[49/49] SOLINK ./libc++.so
FAILED: libc++.so libc++.so.TOC
python "../../build/toolchain/gcc_solink_wrapper.py" --readelf="readelf" --nm="nm" --sofile="./libc++.so" --tocfile="./libc++.so.TOC" --output="./libc++.so"  -- ../../../../clang/bin/clang++ -shared -Wl,--fatal-warnings -fPIC -Wl,-z,noexecstack -Wl,-z,now -Wl,-z,relro -Wl,-z,defs -Wl,--no-as-needed -lpthread -Wl,--as-needed -fuse-ld=lld -Wl,--icf=all -m64 -Wl,--gdb-index -nostdlib++ --sysroot=../../build/linux/debian_jessie_amd64-sysroot -L../../build/linux/debian_jessie_amd64-sysroot/lib/x86_64-linux-gnu -Wl,-rpath-link=../../build/linux/debian_jessie_amd64-sysroot/lib/x86_64-linux-gnu -L../../build/linux/debian_jessie_amd64-sysroot/usr/lib/x86_64-linux-gnu -Wl,-rpath-link=../../build/linux/debian_jessie_amd64-sysroot/usr/lib/x86_64-linux-gnu -Werror -Wl,-u_sanitizer_options_link_helper -o "./libc++.so" -Wl,-soname="libc++.so" @"./libc++.so.rsp"
unimplemented
UNREACHABLE executed at /home/inglorion/llvm/llvm/include/llvm/DebugInfo/DWARF/DWARFObject.h:30!
#0 0x0000000000e63cbf llvm::sys::PrintStackTrace(llvm::raw_ostream&) /home/inglorion/llvm/llvm/lib/Support/Unix/Signals.inc:398:13
#1 0x0000000000e63fb6 bool __gnu_cxx::operator!=<std::pair<void (*)(void*), void*>*, std::vector<std::pair<void (*)(void*), void*>, std::allocator<std::pair<void (*)(void*), void*> > > >(__gnu_cxx::__normal_iterator<std::pair<void (*)(void*), void*>*, std::vector<std::pair<void (*)(void*), void*>, std::allocator<std::pair<void (*)(void*), void*> > > > const&, __gnu_cxx::__normal_iterator<std::pair<void (*)(void*), void*>*, std::vector<std::pair<void (*)(void*), void*>, std::allocator<std::pair<void (*)(void*), void*> > > > const&) /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/bits/stl_iterator.h:825:27
#2 0x0000000000e63fb6 llvm::sys::RunSignalHandlers() /home/inglorion/llvm/llvm/lib/Support/Signals.cpp:49:0
#3 0x0000000000e63fb6 SignalHandler(int) /home/inglorion/llvm/llvm/lib/Support/Unix/Signals.inc:242:0
#4 0x00007fd4accaa330 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x10330)
#5 0x00007fd4ab899c37 gsignal /build/eglibc-SvCtMH/eglibc-2.19/signal/../nptl/sysdeps/unix/sysv/linux/raise.c:56:0
#6 0x00007fd4ab89d028 abort /build/eglibc-SvCtMH/eglibc-2.19/stdlib/abort.c:91:0
#7 0x0000000000e18469 (/home/inglorion/chromium/src/out/repro/../../../../clang/bin/ld.lld+0xe18469)
#8 0x0000000000f02fd9 (/home/inglorion/chromium/src/out/repro/../../../../clang/bin/ld.lld+0xf02fd9)
#9 0x000000000107bcac llvm::DWARFContext::getDWOContext(llvm::StringRef)::$_5::operator()() const /home/inglorion/llvm/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp:930:24
#10 0x000000000107bcac llvm::DWARFContext::getDWOContext(llvm::StringRef) /home/inglorion/llvm/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp:925:0
#11 0x000000000109b8c9 std::__shared_ptr<llvm::DWARFContext, (__gnu_cxx::_Lock_policy)2>::operator bool() const /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/bits/shared_ptr_base.h:923:16
#12 0x000000000109b8c9 llvm::DWARFUnit::parseDWO() /home/inglorion/llvm/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp:293:0
#13 0x000000000109bbbb llvm::DWARFUnit::collectAddressRanges(std::vector<llvm::DWARFAddressRange, std::allocator<llvm::DWARFAddressRange> >&) /home/inglorion/llvm/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp:335:21
#14 0x0000000000f7e1b1 readAddressAreas(llvm::DWARFContext&, lld::elf::InputSection*) /home/inglorion/llvm/lld/ELF/SyntheticSections.cpp:1937:50
#15 0x0000000000f7f205 lld::elf::GdbIndexSection* lld::elf::createGdbIndex<llvm::object::ELFType<(llvm::support::endianness)1, true> >()::{lambda(unsigned long)#1}::operator()(unsigned long) const /home/inglorion/llvm/lld/ELF/SyntheticSections.cpp:2029:5
#16 0x0000000000ed4b0a std::function<void (unsigned long)>::operator()(unsigned long) const /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/functional:2471:14
#17 0x0000000000ed4b0a void llvm::parallel::for_each_n<llvm::parallel::parallel_execution_policy, unsigned long, std::function<void (unsigned long)> >(llvm::parallel::parallel_execution_policy, unsigned long, unsigned long, std::function<void (unsigned long)>) /home/inglorion/llvm/llvm/include/llvm/Support/Parallel.h:218:0
#18 0x0000000000ed4b0a lld::parallelForEachN(unsigned long, unsigned long, std::function<void (unsigned long)>) /home/inglorion/llvm/lld/include/lld/Common/Threads.h:79:0
#19 0x0000000000f5b446 std::_Function_base::~_Function_base() /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/functional:2029:11
#20 0x0000000000f5b446 lld::elf::GdbIndexSection* lld::elf::createGdbIndex<llvm::object::ELFType<(llvm::support::endianness)1, true> >() /home/inglorion/llvm/lld/ELF/SyntheticSections.cpp:2023:0
#21 0x0000000000fac192 (anonymous namespace)::Writer<llvm::object::ELFType<(llvm::support::endianness)1, true> >::createSyntheticSections() /home/inglorion/llvm/lld/ELF/Writer.cpp:357:19
#22 0x0000000000fac192 (anonymous namespace)::Writer<llvm::object::ELFType<(llvm::support::endianness)1, true> >::run() /home/inglorion/llvm/lld/ELF/Writer.cpp:162:0
#23 0x0000000000faabc2 std::_Vector_base<lld::elf::PhdrEntry*, std::allocator<lld::elf::PhdrEntry*> >::~_Vector_base() /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/bits/stl_vector.h:160:37
#24 0x0000000000faabc2 std::vector<lld::elf::PhdrEntry*, std::allocator<lld::elf::PhdrEntry*> >::~vector() /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/bits/stl_vector.h:416:0
#25 0x0000000000faabc2 (anonymous namespace)::Writer<llvm::object::ELFType<(llvm::support::endianness)1, true> >::~Writer() /home/inglorion/llvm/lld/ELF/Writer.cpp:39:0
#26 0x0000000000faabc2 void lld::elf::writeResult<llvm::object::ELFType<(llvm::support::endianness)1, true> >() /home/inglorion/llvm/lld/ELF/Writer.cpp:131:0
#27 0x0000000000ec844b void lld::elf::LinkerDriver::link<llvm::object::ELFType<(llvm::support::endianness)1, true> >(llvm::opt::InputArgList&) /home/inglorion/llvm/lld/ELF/Driver.cpp:1146:1
#28 0x0000000000ec1da6 lld::elf::LinkerDriver::main(llvm::ArrayRef<char const*>, bool) /home/inglorion/llvm/lld/ELF/Driver.cpp:407:5
#29 0x0000000000ec0c9b lld::elf::link(llvm::ArrayRef<char const*>, bool, llvm::raw_ostream&) /home/inglorion/llvm/lld/ELF/Driver.cpp:96:3
#30 0x0000000000e1735a main /home/inglorion/llvm/lld/tools/lld/lld.cpp:116:13
#31 0x00007fd4ab884f45 __libc_start_main /build/eglibc-SvCtMH/eglibc-2.19/csu/libc-start.c:321:0
#32 0x0000000000e17029 _start (/home/inglorion/chromium/src/out/repro/../../../../clang/bin/ld.lld+0xe17029)
Stack dump:
0.      Program arguments: /home/inglorion/chromium/src/out/repro/../../../../clang/bin/ld.lld --sysroot=../../build/linux/debian_jessie_amd64-sysroot -z relro --hash-style=gnu --eh-frame-hdr -m elf_x86_64 -shared -o ./libc++.so ../../build/linux/debian_jessie_amd64-sysroot/usr/lib/gcc/x86_64-linux-gnu/4.8/../../../x86_64-linux-gnu/crti.o ../../build/linux/debian_jessie_amd64-sysroot/usr/lib/gcc/x86_64-linux-gnu/4.8/crtbeginS.o -L../../build/linux/debian_jessie_amd64-sysroot/lib/x86_64-linux-gnu -L../../build/linux/debian_jessie_amd64-sysroot/usr/lib/x86_64-linux-gnu -L../../build/linux/debian_jessie_amd64-sysroot/usr/lib/gcc/x86_64-linux-gnu/4.8 -L../../build/linux/debian_jessie_amd64-sysroot/usr/lib/gcc/x86_64-linux-gnu/4.8/../../../x86_64-linux-gnu -L../../build/linux/debian_jessie_amd64-sysroot/lib/x86_64-linux-gnu -L../../build/linux/debian_jessie_amd64-sysroot/lib/../lib64 -L../../build/linux/debian_jessie_amd64-sysroot/usr/lib/x86_64-linux-gnu -L../../build/linux/debian_jessie_amd64-sysroot/usr/lib/gcc/x86_64-linux-gnu/4.8/../../.. -L../../build/linux/debian_jessie_amd64-sysroot/lib -L../../build/linux/debian_jessie_amd64-sysroot/usr/lib --fatal-warnings -z noexecstack -z now -z relro -z defs --no-as-needed -lpthread --as-needed --icf=all --gdb-index -rpath-link=../../build/linux/debian_jessie_amd64-sysroot/lib/x86_64-linux-gnu -rpath-link=../../build/linux/debian_jessie_amd64-sysroot/usr/lib/x86_64-linux-gnu -u_sanitizer_options_link_helper -soname=libc++.so --whole-archive obj/buildtools/third_party/libc++/libc++/algorithm.o obj/buildtools/third_party/libc++/libc++/any.o obj/buildtools/third_party/libc++/libc++/bind.o obj/buildtools/third_party/libc++/libc++/chrono.o obj/buildtools/third_party/libc++/libc++/condition_variable.o obj/buildtools/third_party/libc++/libc++/debug.o obj/buildtools/third_party/libc++/libc++/exception.o obj/buildtools/third_party/libc++/libc++/functional.o obj/buildtools/third_party/libc++/libc++/future.o obj/buildtools/third_party/libc++/libc++/hash.o obj/buildtools/third_party/libc++/libc++/ios.o obj/buildtools/third_party/libc++/libc++/iostream.o obj/buildtools/third_party/libc++/libc++/locale.o obj/buildtools/third_party/libc++/libc++/memory.o obj/buildtools/third_party/libc++/libc++/mutex.o obj/buildtools/third_party/libc++/libc++/new.o obj/buildtools/third_party/libc++/libc++/optional.o obj/buildtools/third_party/libc++/libc++/random.o obj/buildtools/third_party/libc++/libc++/regex.o obj/buildtools/third_party/libc++/libc++/shared_mutex.o obj/buildtools/third_party/libc++/libc++/stdexcept.o obj/buildtools/third_party/libc++/libc++/string.o obj/buildtools/third_party/libc++/libc++/strstream.o obj/buildtools/third_party/libc++/libc++/system_error.o obj/buildtools/third_party/libc++/libc++/thread.o obj/buildtools/third_party/libc++/libc++/typeinfo.o obj/buildtools/third_party/libc++/libc++/utility.o obj/buildtools/third_party/libc++/libc++/valarray.o obj/buildtools/third_party/libc++/libc++/variant.o obj/buildtools/third_party/libc++/libc++/vector.o obj/buildtools/third_party/libc++abi/libc++abi/abort_message.o obj/buildtools/third_party/libc++abi/libc++abi/cxa_aux_runtime.o obj/buildtools/third_party/libc++abi/libc++abi/cxa_default_handlers.o obj/buildtools/third_party/libc++abi/libc++abi/cxa_demangle.o obj/buildtools/third_party/libc++abi/libc++abi/cxa_exception.o obj/buildtools/third_party/libc++abi/libc++abi/cxa_exception_storage.o obj/buildtools/third_party/libc++abi/libc++abi/cxa_guard.o obj/buildtools/third_party/libc++abi/libc++abi/cxa_handlers.o obj/buildtools/third_party/libc++abi/libc++abi/cxa_personality.o obj/buildtools/third_party/libc++abi/libc++abi/cxa_unexpected.o obj/buildtools/third_party/libc++abi/libc++abi/cxa_vector.o obj/buildtools/third_party/libc++abi/libc++abi/cxa_virtual.o obj/buildtools/third_party/libc++abi/libc++abi/fallback_malloc.o obj/buildtools/third_party/libc++abi/libc++abi/private_typeinfo.o obj/buildtools/third_party/libc++abi/libc++abi/stdlib_exception.o obj/buildtools/third_party/libc++abi/libc++abi/stdlib_stdexcept.o obj/build
clang-6.0: error: unable to execute command: Aborted (core dumped)
clang-6.0: error: linker command failed due to signal (use -v to see invocation)
ninja: build stopped: subcommand failed.

Filed LLVM bug https://bugs.llvm.org/show_bug.cgi?id=35199

This was fixed in Clang 318519.