Don't try to force use of -no-cpp-precomp on OS X. It's been five years

since Apple shipped a compiler that needed this switch, and there's
increasing interest in using other compilers that won't accept the switch
at all.  Better to let anybody who still needs the switch inject it via
CPPFLAGS.  Per gripe from Neil Conway.

src/template/darwin

-# $PostgreSQL: pgsql/src/template/darwin,v 1.11 2007/09/26 00:32:46 tgl Exp $
-
-# Apple's cpp-precomp seems a tad broken, so don't use it
-# (Note: on OS X before 10.2, you might need -traditional-cpp instead)
-CC="$CC -no-cpp-precomp"
+# $PostgreSQL: pgsql/src/template/darwin,v 1.12 2010/08/02 04:51:17 tgl Exp $
 
 # Select appropriate semaphore support.  Darwin 6.0 (Mac OS X 10.2) and up
 # support System V semaphores; before that we have to use POSIX semaphores,