[PerfSuite-users] Re: PerfSuite: psrun and 32bit code on x86_64

[Rick K. <rk...@nc...>]

Alex (and others),

Here's a followup on your question below regarding using PerfSuite with 
32-bit binaries on AMD64.  In general, it seems that it won't be too 
difficult to incorporate this in an upcoming release although the current 
versions won't build cleanly as-is and will have a few adjustments made 
to deal with things better.  As far as I can tell, there isn't a standard 
for filesystem names for 32- or 64-bit libraries, so it'll be the choice 
of the person building it ("--libdir=" configure-time option).

I'm working on RHEL4 (Nahant Update 1), Opteron 248, and currently have 
run into an issue that I'm hoping you or others on this list might be able
to offer a suggestion/workaround.  Specifically, linking a program compiled
for 32-bit fails in finding the Expat library (-lexpat, which is actually 
present in both of /usr/lib and /usr/lib64).  It seems to me that the 
linker search path isn't what it should be, even though -m32 is on the 
compile/link line.  This, in turn, is messing up a creation of the 
"libpshwpc" shared library which is where Expat is used in PerfSuite.

What I'm after are any suggestions that would successfully compile and 
link the following program as a 32-bit app on AMD64.  Once this gets 
solved, things should be on their way.  If there isn't a clean way to fix 
it, I think it'll still be possible to have 32-bit support but would 
require hand-editing automake-generated makefiles, which is naturally not 
too pleasant...

Thanks in advance for any suggestions!

Rick

Error output from the link is:

# gcc -m32 -o expattest expattest.c -lexpat
/usr/bin/ld: skipping incompatible /usr/lib64/libexpat.so when searching for -lexpat
/usr/bin/ld: skipping incompatible /usr/lib64/libexpat.a when searching for -lexpat
/usr/bin/ld: cannot find -lexpat
collect2: ld returned 1 exit status

Explicitly adding -L/usr/lib or setting LDEMULATION don't seem to do the 
trick for me.  The only thing I've found that works is to add 
/usr/lib/libexpat.so.0 on the link line instead of -lexpat :(

-----------------------------
#include <stdlib.h>
#include <stdio.h>
#include <expat.h>

main(int argc, char **argv)
{
    XML_Parser p;

    p = XML_ParserCreate(NULL);
    if ( ! p ) {
        fputs("Error in creating parser\n", stderr);
        exit(1);
    }
    exit(0);
}


On Mon, 18 Jul 2005, Alex Mericas wrote:

> I am running Suse on an Athlon64.  I can use psrun without problems on binaries compiled for 64bit, but if I try to run 32bit binaries psrun cannot find its runtime library.  I'm guessing psrun would need both a 32bit and a 64bit library to work this way.  Is this possible?  Do you have plans to implement?  Thanks!
>