Support --rpath-link option

       -rpath-link=dir
           When using ELF or SunOS, one shared library may require another.  This happens when an "ld -shared" link includes a shared library as one of the input files.

           When the linker encounters such a dependency when doing a non-shared, non-relocatable link, it will automatically try to locate the required shared library and include it in the link, if it is not
           included explicitly.  In such a case, the -rpath-link option specifies the first set of directories to search.  The -rpath-link option may specify a sequence of directory names either by
           specifying a list of names separated by colons, or by appearing multiple times.

           This option should be used with caution as it overrides the search path that may have been hard compiled into a shared library. In such a case it is possible to use unintentionally a different
           search path than the runtime linker would do.

           The linker uses the following search paths to locate required shared libraries:

           1.  Any directories specified by -rpath-link options.

           2.  Any directories specified by -rpath options.  The difference between -rpath and -rpath-link is that directories specified by -rpath options are included in the executable and used at runtime,
               whereas the -rpath-link option is only effective at link time. Searching -rpath in this way is only supported by native linkers and cross linkers which have been configured with the
               --with-sysroot option.

           3.  On an ELF system, for native linkers, if the -rpath and -rpath-link options were not used, search the contents of the environment variable "LD_RUN_PATH".

           4.  On SunOS, if the -rpath option was not used, search any directories specified using -L options.

           5.  For a native linker, the search the contents of the environment variable "LD_LIBRARY_PATH".

           6.  For a native ELF linker, the directories in "DT_RUNPATH" or "DT_RPATH" of a shared library are searched for shared libraries needed by it. The "DT_RPATH" entries are ignored if "DT_RUNPATH"
               entries exist.

           7.  The default directories, normally /lib and /usr/lib.

           8.  For a native linker on an ELF system, if the file /etc/ld.so.conf exists, the list of directories found in that file.

           If the required shared library is not found, the linker will issue a warning and continue with the link.
Original issue reported on code.google.com by pete.c...@gmail.com on 7 Jan 2013 at 7:07
send2vinnie / mclinker

Support --rpath-link option #119
