[Bug target/96607] GCC feeds SPARC/Solaris linker with unrecognized TLS sequences

["ro at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96607

Rainer Orth <ro at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |ebotcazou at gcc dot gnu.org,
                   |                            |ro at gcc dot gnu.org

--- Comment #1 from Rainer Orth <ro at gcc dot gnu.org> ---
To add some background: I've been experiencing ca. 250 test failures in the
LLVM
testsuite when building for sparcv9-sun-solaris2.11.

As a workaround, I've posted

  [cmake] Don't build with -O3 -fPIC on Solaris/sparcv9
  https://reviews.llvm.org/D85630

based on the observation that the SEGVs vanish if LLVM is compiled with -O
-fPIC
only instead of the default -O3 -fPIC.

I've been using the following slightly reduced example (attached):

* tqt.cpp is reduced from LLVM's llvm/unittests/Support/TaskQueueTest.cpp.

* ThreadPool.cpp is LLVM 10.0.0 llvm/lib/Support/ThreadPool.cpp.

They can be compiled and linked with the included tqt.sh; however that relies
on
LLVM 10 bundled with Solaris 11.4 for LLVM headers, libLLVMSupport and
libLLVMDemangle.

I haven't tried to produce a further reduced example yet.