Bob, I definitely have -pthread in there, std::thread isn't defined with out it. Jonathan, I was pulling together the linker command line to post and realized that I had a -L directive that points to a directory containing libstdc++, but it was the gcc 5.3.0 libstdc++. I did this because it's the only way to get an rpath-type thing in the resulting binary. Of course, once I removed this everything linked properly. Sorry to be a bother and thanks for the quick replies!! On Thu, May 24, 2018 at 6:01 AM, Jonathan Wakely <jwakely.gcc@xxxxxxxxx> wrote: > On 24 May 2018 at 02:44, Brian Groose wrote: >> I'm moving from g++ 5.3.0 to 8.1.0 at the moment, and bumped into an >> unexpected linker failure on AIX. I don't currently have a small >> piece of code that reproduces the issue, but I'm working on narrowing >> it down. Hopefully someone can make a suggestion without code, >> though. I've build gcc 8.1.0 from source with no special options >> except --prefix and --enable-languages=c,c++ >> >> These are the AIX linker errors using g++ 8.1.0: >> ld: 0711-317 ERROR: Undefined symbol: typeinfo for std::thread::_State >> ld: 0711-317 ERROR: Undefined symbol: .std::thread::_State::~_State() >> ld: 0711-317 ERROR: Undefined symbol: >> .std::thread::_M_start_thread(std::unique_ptr<std::thread::_State, >> std::default_delete<std::thread::_State> >, void (*)()) >> ld: 0711-317 ERROR: Undefined symbol: vtable for std::thread::_State >> >> This worked fine, the same code, on g++ 5.3.0. >> >> This looks similar to >> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=52887 except for >> std::thread. It seems to happen when std::thread is used to call a >> member function, though a simple test case worked fine. > > That bug was fixed by adding explicit instantiations to the library, > but the undefined symbols you're seeing are not templates, and are > defined in libstdc++.so > > The only way those symbols would not be in libstdc++.so is if this > condition is false when building libstdc++.so but true when compiling > your own code: > > #if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1) > > > Alternatively, you're simply not linking to libstdc++ correctly (or at > all). What is your linker command that fails?
