Re: ld option for setting runtime libpath for AIX

[Kevin Heatwole <kdh at ocsystems dot com>]

Thanks for the reply, but...

This is the way it works on AIX, but the GNU ld cross (I'm running on 
LinuxPPC) doesn't do anything with LIBPATH.

For example, I just tried:

$ export LIBPATH=/usr/lib:/lib
$ /work/build/gcc-aix-cross/rs6000-ibm-aix4.2.1.0/bin/gcc hello.c

on the LinuxPPC box and then dumped the a.out header on the AIX box:

$ dump -H a.out

a.out:

                         ***Loader Section***
                       Loader Header Information
VERSION#         #SYMtableENT     #RELOCent        LENidSTR
0x00000001       0x00000007       0x00000017       0x0000010c

#IMPfilID        OFFidSTR         LENstrTBL        OFFstrTBL
0x00000002       0x000001dc       0x0000000d       0x000002e8


                         ***Import File Strings***
INDEX  PATH                          BASE                MEMBER
0      /work/build/gcc-aix-cross/lib/gcc-lib/rs6000-ibm-
aix4.2.1.0/2.95.3:/work/build/gcc-aix-cross/rs6000-ibm-
aix4.2.1.0/lib/rs6000-ibm-aix4.2.1.0/2.95.3:/work/build/gcc-aix-
cross/rs6000-ibm-aix4.2.1.0/lib:/work/build/gcc-aix-
cross/rs6000-ibm-aix4.2.1.0/lib
1                                    libc.a              shr.o

The default search path is still stored in the binary and no sign of 
/usr/lib or /lib.

Now, if I set LIBPATH at runtime, the a.out will load, but I want to be 
able to set this default path at bind time so the user doesn't have to 
do anything special to get it to load.

I do have the workaround of specifying -L/usr/lib and -L/lib on the 
bind, but this just adds to the default libpath and does not clear it.

I really want the equivalent of -blibpath option that AIX ld has (or 
like the rpath option for ELF binaries).  I suppose I could start 
looking at the source.  It would seem to be a trivial option to 
implement, if it is not supported now.

Any other ideas?

Kevin

On Wednesday, October 24, 2001, at 10:55  PM, Tom Rix wrote:

> I believe you can do something like
>
> export LIBPATH=$NEWLIBPATH.
> And this string will appear as the first and default library path to be
> used as the system loader.   See Loader Section Import File ID's in the
> xcoff spec.
>
> Tom
>
>
> Kevin Heatwole wrote:
>
>> I'm looking for the equivalent AIX ld to option -blibpath:/lib:/usr/lib
>> for GNU ld for AIX.  Specifically, I want to override the default
>> LIBPATH stored in executables to just look in the directories
>> "/lib:/usr/lib".
>>
>> Does anyone know if there is such an equivalent option or linker 
>> command
>> to set this value in executables bound with GNU ld for AIX?
>>
>> I know about adding directories with -L or SEARCH_DIR, but I want to
>> replace the whole default LIBPATH.  I also know that the AIX loader 
>> uses
>> the environment variable LIBPATH to override the value stored in the
>> binary.
>>
>> But, neither of these workarounds is quite what I want to do.
>>
>> Hope someone can point me to something that allows, at link-time, to 
>> set
>> the runtime LIBPATH for AIX executables that is stored in the
>> executables.  Thanks in advance for any help here.
>>
>> I'm using a snapshot of binutils (binutils-011017.tar) built as a cross
>> to rs6000-ibm-aix4.2.1.0 hosted on a LinuxPPC machine (since
>> binutils-2.11 seemed to indicate that there are bad bugs in ld for 
>> AIX).
>>
>> Kevin Heatwole
>> OC Systems, Inc.
>
> --
> Tom Rix
> GCC Engineer
> trix@redhat.com
> 256.704.9201
>
>
>