Re: libstdc++/6913: <fstream> totally broken?

["David Abrahams" <david.abrahams@rcn.com>]

The following reply was made to PR libstdc++/6913; it has been noted by GNATS.

From: "David Abrahams" <david.abrahams@rcn.com>
To: "Phil Edwards" <phil@jaj.com>
Cc: <gcc-bugs@gcc.gnu.org>,
	<gcc-gnats@gcc.gnu.org>
Subject: Re: libstdc++/6913: <fstream> totally broken?
Date: Mon, 3 Jun 2002 09:34:42 -0400

 From: "Phil Edwards" <phil@jaj.com>
 
 
 > On Mon, Jun 03, 2002 at 08:52:19AM -0400, David Abrahams wrote:
 > > The FAQ says
 > >
 > > "Please read the installation instructions for GCC, specifically the
 > > part about not installing newer versions on top of older versions"
 > > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 > >
 > > So I followed the link trying to find that part, but I can't. Having a
 > > mention in the FAQ but nothing [sufficiently visible] in the
 installation
 > > instructions borders on a cruel joke.
 >
 > On the top-level installation page, there's a bit recommending that each
 > GCC get a directory of its own.
 
 The way it's phrased, it sounds like the only reason for that is that you
 might want to un-install it. I won't want to (I have to test against
 multiple versions of GCC) and anyway I assumed that the -V option doesn't
 work to select different versions if you follow that recommendation.
 
 > On one of the pages linked from that page,
 > there should be a paragraph pointing it out in more detail, but I don't
 > recall where offhand.
 
 Yes, there should be. However, I scoured those pages for "version",
 "directory", and "older" and saw nothing relevant.
 
 > If you feel that the existing wording doesn't jump out strongly enough,
 > please do suggest alternates.  Some of us have been reading these pages
 > for so long that we no longer see the words.
 
 This is a no-brainer: in BIG, BOLD letters, on the main installation page
 and on the release pages of the first version which had this problem, and
 several versions thereafter:
 
 <b><font color="#ff0000">CAUTION</font>: installing a new version of GCC
 over another one with a different major or minor version number can cause
 both versions to malfunction. You must pass "--prefix=..." as an argument
 to configure in order to avoid installation conflicts</b>.
 
 Actually, the configure script should take care of detecting this mistake
 and prompting for alternatives.
 
 > > correct system?
 >
 > Easiest way to to just delete the previous installation before running
 > "make install" for the new build.
 
 And how does one do that?
 
 My installation prefix was the default, which appears to have been
 /usr/local. Is there a description somewhere of all the directories and
 files added by a GCC installation? How will I know which files to delete?
 
 > Or, if you don't mind building it again, rebuild with a
 different --prefix.
 
 I don't mind rebuilding at all, so long as I know how to make things work
 correctly.
 
 Thanks for your help,
 Dave