bug in cvs libtool tag detection for same-basename compilers

[Karl Chen]

Hi, I believe there is a bug in libtool (current cvs) for "TAG" detection.

libtool decides which compiler flags to use based on the command line by 
checking the basename of the command-line command and the basename of each 
tag's command. I'm sure you already know that, just making sure we're on 
the same page.

This works for "gcc" and "g++" and "g77" but it doesn't work in a lot of 
other cases. Examples:
    KAI C++:
        "KCC" is a C++ compiler but "KCC --c" is a C compiler. There is no 
command for just C.

    gcc:
         "gcc" is a C compiler as well as C++  and other compiler 
(depending on file extension), although people usually use g++ for C++ just 
to simplify linking. Also "gcc -x c++" is a C++ compiler but that is a 
little contrived anyway.

If I have CC="KCC --c" and CXX="KCC", then libtool will not compile C++ 
programs because it will look at the command line, see "KCC", compare to 
the first tag which happens to be C, whose base commandname is "KCC", and 
decide to compile it as a C program.

One possible more-robust fix using automake is to use "--tag=CXX" to the 
libtool C++ command-line in LTCXX (or whatever); similar for other languages.

Currently I'm kludging around it by having autoconf create a script 
"KCC--c" which just contains a call to "${CXX} --c \"address@hidden"", and set 
CC=KCC--c if "$CC"="$CXX --c".
I'm using KCC 3.4 and 4.0 on osf 5.1.



--
Karl Chen / address@hidden / (925)-422-7509