According to the logs and local debugging there were two issues:
1) tsan tests listed libc++.a before the source file. That's usually
ok for shared libraries, but the linker will not add symbols from
a static library unless needed at that time. As a result the tests
that rely upon symbols from the library (and not only include the
headers) had undefined references.
To solve this I'm adding a new substitution %link_libcxx_tsan which
expands to libc++.a if available.
2) The target Fuzzer-x86_64-Test linked in SANITIZER_TEST_CXX_LIBRARIES
which defaults to -lstdc++. This resulted in error messages like
hidden symbol '_ZdlPv' is not defined locally
hidden symbol '_Znwm' is not defined locally
when using GNU gold (ld.bfd and lld are fine). Removing the linkage
is fine because we build a custom libc++ for that purpose.
llvm-svn: 354231
0a9cb239a6