Re: Embedded Perl & MQSeries

[Salman Mohsin]

I looked at the way I was building my application and I rearranged the  
command-line so that order is exactly reverse to what it was before (I  
wasn't sure if the libraries included 1st or last take the precedence).  
Perl was also using its own "malloc". I re-built perl so that it now uses  
system's malloc instead of its own. The problem is still there.

I'd really appreciate if someone could give me some pointers to rectify  
this problem. Thanks a lot.

Here's how I used to make the application before Perl (in the Makefile):
all: dispatcher
dispatcher: dispatcher.o mqseries.o log.o
        cc -o dispatcher dispatcher.o mqseries.o log.o -Llib -lmqm
dispatcher.o: dispatcher.c mqseries.h bool.h log.h
        cc -c dispatcher.c
mqseries.o: mqseries.h mqseries.c bool.h
        cc -c -Iinclude mqseries.c
log.o: log.h log.c bool.h
        cc -c log.c
Here are the contents of the lib/ and include/ directories:

Mon Jun  7, 12:40:57 $ ls include/
cmqc.h
Mon Jun  7, 12:40:59 $ ls lib/
libmqm.a
Here's how I build it with perl:
all: dispatcher
dispatcher: dispatcher.o mqseries.o log.o
        cc -o dispatcher dispatcher.o mqseries.o log.o -Llib -lmqm `perl  
-MExtUtils::Embed -e ldopts`

dispatcher.o: dispatcher.c mqseries.h bool.h log.h
        cc -c dispatcher.c `perl -MExtUtils::Embed -e ccopts`
mqseries.o: mqseries.h mqseries.c bool.h
        cc -c -Iinclude mqseries.c
log.o: log.h log.c bool.h
        cc -c log.c
Here's the output from "perl -MExtUtils::Embed -e ccopts":
 -D_ALL_SOURCE -D_ANSI_C_SOURCE -D_POSIX_SOURCE -qmaxmem=-1 -qnoansialias  
-DUSE_NATIVE_DLOPEN -I/usr/local/include -q32 -D_LARGE_FILES -qlonglong   
-I/usr/local/lib/perl5/5.8.4/aix/CORE

Here's the output from "perl -MExtUtils::Embed -e ldopts":
  -bE:/usr/local/lib/perl5/5.8.4/aix/CORE/perl.exp  -brtl -L/usr/local/lib  
-b32 /usr/local/lib/perl5/5.8.4/aix/auto/DynaLoader/DynaLoader.a  
-L/usr/local/lib/perl5/5.8.4/aix/CORE -lperl -lbind -lnsl -ldl -lld -lm  
-lcrypt -lc -lbsd

And finally here's the output from perl -V (after re-building it without  
malloc):

Summary of my perl5 (revision 5 version 8 subversion 4) configuration:
  Platform:
    osname=aix, osvers=4.3.3.0, archname=aix
    uname='aix hdndev 3 4 000195334c00 '
    config_args=''
    hint=recommended, useposix=true, d_sigaction=define
    usethreads=undef use5005threads=undef useithreads=undef  
usemultiplicity=undef
    useperlio=define d_sfio=undef uselargefiles=define usesocks=undef
    use64bitint=undef use64bitall=undef uselongdouble=undef
    usemymalloc=n, bincompat5005=undef
  Compiler:
    cc='cc', ccflags ='-D_ALL_SOURCE -D_ANSI_C_SOURCE -D_POSIX_SOURCE  
-qmaxmem=-1 -qnoansialias -DUSE_NATIVE_DLOPEN -I/usr/local/include -q32  
-D_LARGE_FILES -qlonglong',
    optimize=' ',
    cppflags='-D_ALL_SOURCE -D_ANSI_C_SOURCE -D_POSIX_SOURCE -qmaxmem=-1  
-qnoansialias -DUSE_NATIVE_DLOPEN -I/usr/local/include'
    ccversion='3.6.6.0', gccversion='', gccosandvers=''
    intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=4321
    d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=8
    ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='off_t',  
lseeksize=8
    alignbytes=8, prototype=define
  Linker and Libraries:
    ld='ld', ldflags =' -brtl -L/usr/local/lib -b32'
    libpth=/usr/local/lib /lib /usr/lib /usr/ccs/lib
    libs=-lbind -lnsl -ldbm -ldl -lld -lm -lcrypt -lc -lbsd
    perllibs=-lbind -lnsl -ldl -lld -lm -lcrypt -lc -lbsd
    libc=/lib/libc.a, so=a, useshrplib=false, libperl=libperl.a
    gnulibc_version=''
  Dynamic Linking:
    dlsrc=dl_aix.xs, dlext=so, d_dlsymun=undef, ccdlflags='   
-bE:/usr/local/lib/perl5/5.8.4/aix/CORE/perl.exp'
    cccdlflags=' ', lddlflags=' -bhalt:4 -bM:SRE -bI:$(PERL_INC)/perl.exp  
-bE:$(BASEEXT).exp -bnoentry -lc -L/usr/local/lib'

Characteristics of this binary (from libperl):
  Compile-time options: USE_LARGE_FILES
  Built under aix
  Compiled at Jun  7 2004 09:59:53
  @INC:
    /usr/local/lib/perl5/5.8.4/aix
    /usr/local/lib/perl5/5.8.4
    /usr/local/lib/perl5/site_perl/5.8.4/aix
    /usr/local/lib/perl5/site_perl/5.8.4
    /usr/local/lib/perl5/site_perl
    /usr/local/lib/perl5/site_perl/5.005/aix
    /usr/local/lib/perl5/site_perl/5.005
    .
Thanks,
Salman
On Fri, 04 Jun 2004 14:17:56 +0100, Nick Ing-Simmons  
<[EMAIL PROTECTED]> wrote:

Salman Mohsin <[EMAIL PROTECTED]> writes:
That's where the problem started. When I changed my code,  
compiled/linked
it, and then tried to run it, it core dumped at MQCONN(). Somehow even  
if you don't have any Perl related code embedded in your code but still  
you
linked it with embedded perl, it'd core dump at the 1st MQSeries call.  
I'm compiling & linking by adding (as appropriately suggested by  
"perlembed") `perl -MExtUtils::Embed -e ccopts` and `perl  
-MExtUtils::Embed -e ldopts` to my existing compiler and linker  
commands respectively. This also makes sure that I'm  
incorporating/linking Perl into my code exactly the way
actual Perl executable has been built on our system.

Has anyone else seen this problem of perl and MQSeries??
I don't even know what MQSeries is but here is my ¤0.02 anyway.
1. It is possible that ccopts has provied some -D flags that change
   things. In paticular things like:
   -D_LARGEFILE_SOURCE can mean that structs get an "off_t" that is now
   64-bit and mis-match with libraries expectation of 32-bit.
2. Most likely though is that ldopts has added something like -lpthreads
   or some network library which behaves differently.
3. Even if libaries are okay together the _order_ of libraries
   on final LD line can be vital.
4. ldopts often adds -L/usr/local/lib. It is not unknown for  
/usr/local/lib
   to be full of junk.

Given 2..4 it would be helpful to see what your ldopts are, and
the before/after adding ldopts.