[CMake] shared library linking question

[Tim Blechmann]

hi andreas,

>> common/libcommon.so
>> target1/target1
>> target2/target2
>> 
>> both target1 and target2 are linked with libcommon, both work fine in the
>> build directory, the libraries are resolved correctly.
>> 
>> after installing them, they are formatted like:
>> $PREFIX/lib/libcommon.so
>> $PREFIX/bin/target1
>> $PREFIX/bin/target2
>> 
>> now libcommon.so cannot be resolved, probably because the targets are
>> linked with ../common/libcommon.so, so the loader cannot find the shared
>> library. what is the best way to resolve this issue?
> 
> How did you write your cmake file? Usually you'd be using the libcommon
> target name in target_link_libraries for target1 and target2.

in common/ i build libcommon
add_library(libcommon SHARED ...)

in the target directories, i build the target:
add_executable(targetX ...)
target_link_libraries(targetX libcommon)

the targets are built with 
-rdynamic -L../common ../common/libcommon.so Wl,-
rpath,../common:/path/to/common

from my limited understanding of the linking process, it should link with 
-lcommon instead of using ../common/libcommon.so, since the rpath is already 
set to ../common. but how can i tell cmake to do this?


> Additionally
> in newer CMake versions cmake will set the RPATH of the target1/target2
> binaries to point to the directory and changes this RPATH when installing
> everything. Hence the loader should find your library.

i am not completely fluent, how the linking process works. the rpath seems 
to be set correctly, though. just the library is passed with a path relative 
to the targets ...

thanks, tim

-- 
tim at klingt.org
http://tim.klingt.org

I don't write music for sissy ears.
  Charles Ives