My dev environment contains many copies of a shared library. For dev purposes I want to pass to gcc the absolute, or relative path to the shared library; so I do not have lots of -L entries making it easy to pick up the wrong version.

e.g. gcc -o foobar foo.cpp /dependencies/fred/libbar.so

However, I do not want the path /dependencies to be used as the lookup location for the shared library to be placed in the executable. Is there an option so the command above is equivalent to:

gcc -o foobar foo.cpp -L /dependencies/fred -l bar

I am looking for something that is the opposite of -rpath, which includes a path.

CodePudding user response：

Is there an option so the command above is equivalent to

Yes: when linking libbar.so you should set its SONAME:

gcc -fPIC -shared -o libbar.so bar.o -Wl,--soname=libbar.so

Once you've done so, gcc -o foobar foo.cpp /dependencies/fred/libbar.so will record the SONAME instead of the absolute path in the executable, and you will have achieved desired behavior.

You can examine the "what's recorded in the executable" with: readelf -d foobar | grep NEEDED.

CodePudding user response：

A work around is to use patchelf.

Find the paths using

readelf -d foobar 

replace them with patchelf

patchelf --replace-needed /dependencies/fred/libbar.so libbar.so foobar 

Then use

readelf -d foobar 

to confirm that the path has been replaced.