* c-common.c (handle_cleanup_attribute): New.
        (c_common_attributes): Add it.
        * c-decl.c (finish_decl): Honor the cleanup attribute.
        * doc/extend.texi (Variable Attributes): Document it.

        * unwind-c.c: New file.
        * Makefile.in (LIB2ADDEH): Add it.
        * config/t-darwin, config/t-linux, config/t-linux-gnulibc1,
        config/ia64/t-ia64: Likewise.

        * gcc.dg/cleanup-1.c: New.
        * gcc.dg/cleanup-2.c: New.
        * gcc.dg/cleanup-3.c: New.
        * gcc.dg/cleanup-4.c: New.
        * gcc.dg/cleanup-5.c: New.
        * gcc.dg/cleanup-6.c: New.
        * gcc.dg/cleanup-7.c: New.

From-SVN: r67449