[Mingw-users] Running two versions of gcc on same machine

[John B. <joh...@ho...>]

Hello
I have Mingw (gcc-3.4.2) installed in c:\mingw. I have MSYS installed as 
well. I wanted to try the gcc 4.1 at
http://oss.netfarm.it/mplayer/misc/gcc-mingw32-4.1.1.tar.gz. I did the 
following:

I renamed my existing c:\mingw as c:\mingw3 and installed the mingw-4.1 in 
c:\mingw4.
I created etc\fstab3 and etc\fstab4 with c:\mingw3 and c:\mingw4 mounted on 
\mingw. I copied msys.bat end edited each copy to overwrite etc\fstab 
appropriately before starting the MSYS shell.

Initially, I did not rename the mingw4 gcc (called gcc-4.1.exe, etc.). The 
binutils programs never had a version number appended to them.

I ran the configure script for the package that I was trying to build like 
this:

CC=gcc-4.1 ./configure etc.

It did use gcc-4.1, but it seems that gcc-4.1 was looking for header files 
in c:/mingw/include (and not /mingw/include as I expected, because the 
configure script detected libraries that I had not yet installed into 
c:\mingw4. I always assumed that gcc's include path would be relative to the 
directory that the executanle is in.

Eventually, I renamed c:\mingw4 as c:\mingw and removed the version numbers 
from gcc programs (windres tried to execute gcc).

Is there a way for me to run gcc 3.x and gcc 4.x on the same computer and 
easily switch between them by setting the environment appropriately?