Performance Management Guide

Examples

Following is an example that illustrates efficient use of the ld command:

1. To prebind a library, use the following command on the archive file:

   # ld -r libfoo.a -o libfooa.o

2. The compile and bind of the FORTRAN program something.f is as follows:

   # xlf something.f libfooa.o

   Notice that the prebound library is treated as another ordinary input file, not with the usual library identification syntax (-lfoo).

3. To recompile the module and rebind the executable program after fixing a bug, use the following:

   # xlf something.f a.out

4. However, if the bug fix had resulted in a call to a different subroutine in the library, the bind would fail. The following Korn shell script tests for a failure return code and recovers:

   # !/usr/bin/ksh
   # Shell script for source file replacement bind
   #
   xlf something.f a.out
   rc=$?
   if [ "$rc" != 0 ]
   then
   echo "New function added ... using libfooa.o"
   xlf something.o libfooa.o
   fi