On Wed, 18 Mar 2020 at 19:15, Tom N <nospam@xxxxxxxxxxxxxxx> wrote: > > I'm trying to build GCC from source on Mac (darwin) and keep getting this error when --enable-tls is specified: > > > /var/folders/cq/wx4ff_gd0xncqh9qnbzmt2w40000gp/T//ccS0vBm1.s:9:2: error: unsupported symbol modifier > in relocation > leaq __ZN3GTM12_gtm_thr_tlsE@tlsgd(%rip), %rdi > ^ > make[5]: *** [alloc_cpp.lo] Error 1 > > > If I either omit --enable-tls or specify --disable-tls the build succeeds, I would expect the default to be correct for the target i.e. --disable-tls. If enabling it worked correctly, it would be the default. > but then I get synchronization problems in my code which uses std::unique_lock<std::mutex> (namely it seems the synchronization isn't performed). That makes no sense, neither std::mutex nor std::unique_lock uses TLS.
