* c-common.h (enum rid): Add RID_THREAD.
        * c-decl.c (start_decl): Do not set DECL_COMMON for tls variables.
        (grokdeclarator): Grok __thread.
        * c-parse.in (reswords): Add __thread.
        (rid_to_yy): Add RID_THREAD.
        * cp/lex.c (rid_to_yy): Add RID_THREAD.

        * tree.h (DECL_THREAD_LOCAL): New.
        (struct tree_decl): Add thread_local_flag.
        * print-tree.c (print_node): Dump DECL_THREAD_LOCAL.
        * tree.c (staticp): TLS variables are not static.

        * target-def.h (TARGET_HAVE_TLS): New.
        * target.h (have_tls): New.
        * output.h (SECTION_TLS): New.
        * varasm.c (assemble_variable): TLS variables can't be common for now.
        (default_section_type_flags): Handle .tdata and .tbss.
        (default_elf_asm_named_section): Handle SECTION_TLS.
        (categorize_decl_for_section): Handle DECL_THREAD_LOCAL.

        * flags.h (flag_tls_default): Declare.
        * toplev.c (flag_tls_default): Define.
        (display_help): Display help for it.
        (decode_f_option): Set it.

        * doc/extend.texi (Thread-Local): New node describing language-level
        thread-local storage.
        * doc/invoke.texi (-ftls-model): Document.

        * fixinc/inclhack.def (thread_keyword): New.
        * fixinc/fixincl.x: Rebuild.

From-SVN: r53715