(STARTFILE_SPEC, LINK_SPEC): Don't use
crtbegin.o, crtend.o, crtn.o, libp.a.  Use gcrt0.0, not gcrt1.o.
(ENDFILE_SPEC): Use crtn.o.
(CPP_PREDEFINES): Delete _AIX.
(CPP_SPEC): Add _AIX, _I386, _MBCS.  Handle -posix.
(ASM_SPEC): Turned off.

From-SVN: r4551