This was approved for 3.4 BIB branch. But since it is dead now, I am putting
this in mainline sources.

2002-12-19  Devang Patel  <dpatel@apple.com>
      * gcc.c (struct default_compiler): Recognizes input file name with
      .CPP extension as C++ source files
      * cp/lang-spec.h: Same
      * doc/invoke.texi:  Add documentation for .CPP support.

From-SVN: r60330