Linking issue

[jesperpedersen]

A linking problem

[jpedersen@localhost libcoz]$ ldd ./libcoz.so 
    linux-vdso.so.1 (0x00007ffeb151a000)
    libdl.so.2 => /lib64/libdl.so.2 (0x00007f70e342c000)
    librt.so.1 => /lib64/librt.so.1 (0x00007f70e3422000)
    libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f70e3401000)
    libelf++.so.0 => not found
    libdwarf++.so.0 => not found
    libstdc++.so.6 => /lib64/libstdc++.so.6 (0x00007f70e3207000)
    libm.so.6 => /lib64/libm.so.6 (0x00007f70e30bf000)
    libgcc_s.so.1 => /lib64/libgcc_s.so.1 (0x00007f70e30a5000)
    libc.so.6 => /lib64/libc.so.6 (0x00007f70e2edf000)
    /lib64/ld-linux-x86-64.so.2 (0x00007f70e34db000)

[jpedersen@localhost libcoz]$ locate libelf++.so
/usr/local/lib/libelf++.so
/usr/local/lib/libelf++.so.0

Adding

-       @$(CXX) -shared $(LDFLAGS) -o $@ $^ $(LDLIBS)
+       @$(CXX) -shared $(LDFLAGS) -o $@ $^ $(LDLIBS) -Wl,-rpath,/usr/local/lib

fixes the linking issue.

[ccurtsinger]

What distribution and version of Linux are you running? Did you install libelfin-dev with apt, or from source?

[jesperpedersen]

Fedora 30, installed from source. Kernel is Linux version 5.2.17-200.fc30.x86_64 atm

[jesperpedersen]

An idea could be to switch to a cmake build environment using find macros for the libraries, and let cmake handle the relocation paths

[miguelraz]

I had the same issue as @jesperpedersen on both Ubuntu 18 and latest Fedora stable.

[ccurtsinger]

Pull request #140 switches to using pkg-config to generate libelfin flags, which should account for the installation directory. Hopefully that resolves your issue. If not, then there may be some quirk in libelfin's install target.

[jesperpedersen]

While pkg-config --cflags / --libs solves the compile time problem it doesn't the linking issue, as the relocation paths aren't correctly defined. E.g.

-       @$(CXX) -shared $(LDFLAGS) -o $@ $^ $(LDLIBS)
+       @$(CXX) -shared $(LDFLAGS) -o $@ $^ $(LDLIBS) -Wl,-rpath,/usr/local/lib