[boost] [Boost.build] Install_name wrong on OS X dylibs with latest CVS

From: Mike Jackson (imikejackson_at_[hidden])
Date: 2008-02-01 10:33:21

I just checked out and built boost on OS X 10.4 and there is a  
problem with the "install_name" or "rpath" on the dynamic libraries  
that are built. The "install_name" that is embedded in the libraries  
are basically useless as they do not contain a correct path to the  
libraries. Example for the filesystem is:

532:[mjackson_at_Thor:boost]$ otool -L /Users/Shared/Sandbox/boost- 
install/lib/libboost_filesystem-1_35.dylib
/Users/Shared/Sandbox/boost-install/lib/libboost_filesystem-1_35.dylib:
         bin.v2/libs/filesystem/build/darwin/release/ 
libboost_filesystem-1_35.dylib (compatibility version 0.0.0, current  
version 0.0.0)
         bin.v2/libs/system/build/darwin/release/ 
libboost_system-1_35.dylib (compatibility version 0.0.0, current  
version 0.0.0)
         /usr/lib/libstdc++.6.dylib (compatibility version 7.0.0,  
current version 7.4.0)
         /usr/lib/libgcc_s.1.dylib (compatibility version 1.0.0,  
current version 1.0.0)
         /usr/lib/libSystem.B.dylib (compatibility version 1.0.0,  
current version 88.3.9)

There are a couple of choices for the "Correct" value. The best  
(IMHO) would be to put in the absolute path to the installed library,  
so on my system that would be:

/Users/Shared/Sandbox/boost-install/lib/libboost_filesystem-1_35.dylib

We could also put _no_ path on the install_name, but that requires  
the user to additionally set the DYLD_LIBRARY_PARH which Apple  
discourages.

The fix would be to add the following to the "actions link.dll bind  
LIBRARIES" section of the boost/tools/build/v2/tools/darwin.jam file:

-headerpad_max_install_names -install_name  
"{Install_prefix_lib_location}$(<[1]:D=:S=.dylib)" .....

I do not know anything about bjam so I have no idea how to get the  
"Install_prefix_lib_location". Could some one tell me how to get at  
that value somehow and I will create a patch.

--
Mike Jackson
OS X Build Specialist