PCH merge bootstrap failure on systems without flex

[Mark Mitchell]

> We do that e.g. for autoconf and automake output, but not for bison
> generated files (in CVS.)  But those are more fundamental to the build
> process I guess.  Do you think we should include the flex output in
> CVS?

Definitely not.

In fact, we should consider removing *all* generated files from CVS
at some point, including "configure".  (Unfortunately, right now,
differents parts of the tree require different versions of autoconf.)

We want generated files in tar files so that you can build GCC from
a release tarball with a minimum of installed tools.  We don't want
them in CVS because we assume people using CVS are developers and we
assume developers can get the tools.  And having the generated files
in CVS has lead to all kinds of problems over time.

We've had this debate before; let's not to it again.

-- 
Mark Mitchell                mark@codesourcery.com
CodeSourcery, LLC            http://www.codesourcery.com