* Makefile.in (xcpp, cppspec.o): New targets.
(CPP_INSTALL_NAME): New macro.
(install-cpp): Install xcpp. Use CPP_INSTALL_NAME.
(all.build, start.encap): Build xcpp.
* cppspec.c: New file, implements argument filtering for a
user-visible C preprocessor.
* cpp.sh: Removed.
From-SVN: r26007