Remove TLS configure tests.

There seemed to be support in response to
<https://sourceware.org/ml/libc-alpha/2015-10/msg00510.html> for
removing configure tests that exist only to produce errors, where we
expect that tool versions failing the tests would also fail the tests
of minimum GCC / binutils versions.

This patch removes the tests for TLS support as one instance of such
tests.  Since the addition of TLS emulation support in GCC 4.3, I
don't think these tests would have failed even if proper TLS support
(as required by glibc) was missing in that architecture's GCC back
end, so any new glibc ports wanting a substantive test (if there are
actual GCC or binutils versions for those architectures, with
supported version numbers, missing TLS support) would have needed an
architecture-specific test anyway.

Tested for x86_64 and x86 (testsuite, and that installed shared
libraries are unchanged by the patch).

	* configure.ac (libc_cv_gcc___thread): Remove configure test.
	(libc_cv_gcc_tls_model_attr): Likewise.
	* configure: Regenerated.

1 files changed, 0 insertions, 30 deletions

diff --git a/configure.ac b/configure.ac
index 4879c48db7..1be44f596e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1564,36 +1564,6 @@ if test "$libc_cv_gcc_builtin_redirection" = no; then
   AC_MSG_ERROR([support for the symbol redirection needed])
 fi
 
-dnl Check whether the compiler supports the __thread keyword.
-AC_CACHE_CHECK([for __thread], libc_cv_gcc___thread,
-[cat > conftest.c <<\EOF
-__thread int a = 42;
-EOF
-if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -c conftest.c >&AS_MESSAGE_LOG_FD]); then
-  libc_cv_gcc___thread=yes
-else
-  libc_cv_gcc___thread=no
-fi
-rm -f conftest*])
-if test "$libc_cv_gcc___thread" = no; then
-  AC_MSG_ERROR([support for the __thread keyword is required])
-fi
-
-dnl Check whether the compiler supports the tls_model attribute.
-AC_CACHE_CHECK([for tls_model attribute], libc_cv_gcc_tls_model_attr, [dnl
-cat > conftest.c <<\EOF
-extern __thread int a __attribute__((tls_model ("initial-exec")));
-EOF
-if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -S -Werror conftest.c >&AS_MESSAGE_LOG_FD]); then
-  libc_cv_gcc_tls_model_attr=yes
-else
-  libc_cv_gcc_tls_model_attr=no
-fi
-rm -f conftest*])
-if test "$libc_cv_gcc_tls_model_attr" = no; then
-  AC_MSG_ERROR([support for the tls_model attribute is required])
-fi
-
 dnl Determine how to disable generation of FMA instructions.
 AC_CACHE_CHECK([for compiler option to disable generation of FMA instructions],
 	       libc_cv_cc_nofma, [dnl