DEVEL15-cpp-fixes-20080630

DEVEL15-cpp-fixes-20080630

LICENSE BSD

When probing in configure for cpp, use the user's PATH first and then
the /lib and /usr/ccs/lib directories.  Set PATH_CPP instead of CPP,
since the latter is just overwritten by Autoconf.  Use PATH_CPP by
preference in rxgen and when pre-processing assembly, since otherwise
newer gcc will treat the input file as linker input and not do anything
with it.  Don't assume that cpp writes to the second argument; gcc
apparently doesn't always do this.  Instead, redirect standard output.

(cherry picked from commit 1ec104280d4a4b0a7544a99a7366f59cd3a2cc5f)