* c-lang.c (start_cdtor, finish_cdtor): New functions.
        (finish_file): Use them in building constructor/destructor functions.

        * config/alpha/alpha.h (HAS_INIT_SECTION, LD_INIT_SWITCH,
        LD_FINI_SWITCH): Move ...
        * config/alpha/osf.h: ... here.
        * config/alpha/alpha-interix.h: Don't undef them.

From-SVN: r37307