[Bug middle-end/59777] New: Incorrect expansion of TLS arguments in a call

[danglin at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59777

            Bug ID: 59777
           Summary: Incorrect expansion of TLS arguments in a call
           Product: gcc
           Version: 4.8.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: danglin at gcc dot gnu.org
              Host: hppa-unknown-linux-gnu
            Target: hppa-unknown-linux-gnu
             Build: hppa-unknown-linux-gnu

Created attachment 31813
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=31813&action=edit
Testcase.

The attached testcase shows the problem.  Argument expressions containing
a TLS symbol reference need to be precomputed as a call may be needed to
legitimize the address and this may clobber the setup for earlier arguments
causing wrong code.

For example, compilation of the testcase with:
gcc-4.8 -fPIC -DPIC -W -Wall -Wextra -Wshadow -Wformat -Wundef -D_GNU_SOURCE
-O0 cap-ng.c -fPIC -DPIC -o cap-ng
results in the following output:
$ ./cap-ng
cc
m.hdr1 = 0x400015c8
pidaaaa = 0

There seems to be some attempt to handle this in
precompute_register_parameters().