Merge pull request #678 from jack-pappas/patch-5

Allow clang to compile sgen

diff --combined configure.in
index 39665fda8a3348884130e5308bbe19b305280b2a,9e83c6ed6903543106d54dc830e5cbcfb5ce64ba..e6a64719df53e03a6abed179354a329a1a7363c6
--- 1/configure.in
--- 2/configure.in
+++ b/configure.in
@@@ -174,8 -174,9 +174,8 @@@ case "$host" i
                AC_DEFINE(PTHREAD_POINTER_ID, 1, [pthread is a pointer])
                libdl=
                libgc_threads=pthreads
 -              # This doesn't seem to work as of 7.0 on amd64
 -              with_sigaltstack=no
                use_sigposix=yes
 +              has_dtrace=yes
                ;;
        *-*-*openbsd*)
                host_win32=no
@@@ -2959,11 -2960,6 +2959,6 @@@ if test "x$icall_tables" = "xno"; the
     AC_DEFINE(DISABLE_ICALL_TABLES, 1, [Icall tables disabled])
  fi
  
- if test "x$mono_cv_clang" = "xyes"; then
-    # FIXME: This causes many compilation errors
-    with_tls=pthread
- fi
- 
  if test "x$with_tls" = "x__thread"; then
        AC_DEFINE(HAVE_KW_THREAD, 1, [Have __thread keyword])
        # Pass the information to libgc
@@@ -2972,10 -2968,7 +2967,7 @@@
        AC_TRY_COMPILE([static __thread int foo __attribute__((tls_model("initial-exec")));], [
                ], [
                        AC_MSG_RESULT(yes)
-                       # CLANG doesn't support this yet, and it prints warnings about it
-                       if test "x$mono_cv_clang" = "xno"; then
-                               AC_DEFINE(HAVE_TLS_MODEL_ATTR, 1, [tld_model available])
-                       fi
+                       AC_DEFINE(HAVE_TLS_MODEL_ATTR, 1, [tls_model available])
                ], [
                        AC_MSG_RESULT(no)
        ])