使用Makefile对共享库进行单元测试

Question

I'm writing a shared library, which I have written a unit-testing executable. I would like to create a target in the Makefile which will initiate the the testing routine.

The unit-testing executable is linked to the library that's created a moment ago.

When running the executable within Makefile, I get

./starttest: error while loading shared libraries: libllist.so: cannot open shared object file: No such file or directory

Which way is better to approach this issue ?

1. defining LD_LIBRARY_PATH from within the Makefile like this ?

   export LD_LIBRARY_PATH=$(CURDIR)/lib

2. force the user to install the library before running the tests ?

3. Don't start unit-testing from Makefile, the user will do it by himself.

or maybe I missed something and there's even a better way ?

Answer 1

I would use option #1, if all you want is for the unit tests to be invoked through the makefile. Definitely option #2 should not be used, and I don't like option #3 much either.

A fourth alternative is to build your unit test program using the -rpath linker option to encode the location of the shared library into the unit test program. For example if you're using GCC this would be: -Wl,-rpath=$(CURDIR) . This allows the unit test to be invoked from the command line, without needing LD_LIBRARY_PATH etc. to be set.

This isn't a good idea for final binaries (to encode your build directory into them) but it's fine for unit test binaries that you won't be using outside your build directory anyway.