org.sourceware.binutils@pooryorick.com

[org dot sourceware dot binutils at pooryorick dot com]

For the past couple of years, I've been working on building a software
collection which is install-path-agnostic.  It relies on the use of $ORIGIN in
every shared object.  The dollar sign in "$ORIGIN", though, has proven
hazardous. It must be escaped so that it doesn't get eaten by autoconf
(configure).  Then it must be escaped some more so it doesn't get eaten by
Make.  But if Makefile calls make recursively, passing LDFLAGS on the command
line, it must be escaped further.  Then, it must be escaped even more depending
on the whims of the shell scripts that may run as part of a software build.
Finally, it can easily get lost as programs try to communicate their
configuration settings to other builds.  For example, the gtk+ "configure"
script calls "cups-config --libs", the output of which is then interpolated by
autoconf into gtk+/Makefile between double quotes.  If the output contains
"$ORIGIN", or rather, due to Make escaping, "\$$ORIGIN", $$ ends up being
interpreted as the pid of the current shell.

I have documented specific cases of trouble here (including building binutils itself):

    http://ynform.org/w/Pub/TheTroubleWithOrigin

Because of all these troubles, I have resorted to using a pattern like ZZZZZZZ,
and then, when the build is finished, replacing this pattern in the ELF files
with $ORIGIN.  It's a hack that would be nice to avoid.

For the innovation of $ORIGIN to succeed, it needs to be more compatible with
the GNU toolchain.  Last year, Dave Korn pondered providing some
altenate token for binutils to translate into $ORIGIN (http://sourceware.org/ml/binutils/2009-05/msg00258.html).

How about a pattern like the following, which avoids the pitfalls mentioned above:

//ORIGIN/

Or, if that is not improbable enough:

///ORIGIN/

It would only need to be recognized at the beginning of any path to be included
in RPATH/RUNPATH list.

-- 
Yorick