Which version of GCC to use: an example

[Claudio Bley]

>>>>> "Bob" == Bob Gustafson <bobgus@mcs.com> writes:

    Bob> Claudio == Claudio Bley <bley@cs.uni-magdeburg.de> writes:
    >>>>>>> "Bob" == Bob Gustafson <bobgus@mcs.com> writes:
    >>
    Bob> My goal was to compile and install prcs-1.3.1 (a new source
    Bob> code control system)
    >>
    Bob> I started out with gcc version 2.96 which is the stock
    Bob> version supplied with RedHat 7.2 (for i686-pc-linux-gnu)
    >>
    Bob> ./configure 2>&1 | tee config.out make 2>&1 | tee make.out
    >>
    Bob> The last few lines of make.out are:
    >>  [snipped]
    >> 
    Claudio> As Frank Schafer already pointed out, you should never
    Claudio> use gcc 2.96 because there never was such a release.

    Bob> I just used what came with RH 7.2 (However, I am now using
    Bob> 2.95.3)

Okay, but I never understood why RedHat shipped its distribution with
that compiler, nor did I understand why the GCC people called their
development version "2.96".

    >>
    Bob> It still won't make. Last bit of the make.out file is given
    Bob> below ( make 2>&1 | tee make.out).
    >>  [snipped]
    >> 
    Bob> Finally, I installed gcc version 2.95.3 (2.95.3 20010315
    Bob> (release)) and this worked fine.
    >>
    Bob> I don't know if there are bugs in the compiler(s) or bugs in
    Bob> prcs-1.3.1, but this might be a regression test to pass for
    Bob> the newer compilers.
    >>
    Claudio> prcs is not complying with the ANSI C++ Standard as
    Claudio> required by gcc v3. prcs needs to be fixed until you're
    Claudio> able to compile it with gcc v3.

    >> From the listing of make errors, do you have any guidance as to
    >> what part
    Bob> of the ANSI C++ Standard is being violated?

At first, stdiostream.h apparently was removed from the stdc++ lib
distributed with gcc v3. Thus, there is no class `stdiobuf' (I
couldn't find it in "The C++ Standard Library" book nor in any of the
header files of gcc's standard c++ library).

The other errors seem to result due gcc getting confused -- it seems
gcc doesn't recognize the `const' keyword anymore... E.g. in
include/prcserror.h:509: parse error before `char' :

omanip<const char*> query(const char* message);

    Bob> Also, if 2.95.3 does the job, why doesn't 3.0.3 flag (and
    Bob> deprecate) the things that pass 2.95.3 and do not pass 3.0.3
    Bob> :-)

I suppose that would blow up the compiler quite a bit. Eventually, you
would need to distribute a complete gcc v2.95 with it in order to say
"hey, it would compile with gcc v2.95.x but not with the release of
gcc you're using now." It's a lot easier to say: "just write standard
compliant code!".

Claudio