If you are trying to build world on an elf system and you use NOPERL
and a symbolic link from /usr/bin/perl to /usr/local/bin/perl5, your
build _will_ barf.
The problem is that perl5 configures itself for a particular library
path (libpth in it's configure) at build time and appends extra search
paths from LD_LIBRARY_PATH at runtime. If perl5 is executed during a
`make world', it will definititely use the wrong path to load shared
objects. Our build system goes to a lot of trouble to set the paths
so that tools like ld DTRT. AFAIK there is no way to tell perl5, in
the amount of detail required, how to behave at runtime.
This is the problem that Mark Murray has been having with the integration
of the contribified perl5 into the main tree. I believe it is a software
design issue that should be solved in the perl DynaLoader code before we
adopt perl5 for main stream use.