cmake subdirectories install - cmake

Question

I would like to set up a new project using CMake.
My working dir is the following :
CMakeLists.txt
include
- file1.h
src
- file1.cpp
- CMakeLists.txt
tests
- test1.cpp
- CMakeLists.txt
The main CMakeList.txt is the following:
cmake_minimum_required(VERSION 2.8)
project(bench CXX)
include_directories(include)
subdirs(src tests)
The src CMakeList.txt is :
add_library(foo SHARED file1.cpp)
install(TARGETS foo DESTINATION lib)
And the tests CMakeList.txt is:
add_executable(test1 test1.cpp)
target_link_libraries(test1 foo)
install(TARGETS test1 DESTINATION bin)
I would expect the files to be located in
<build_dir>/bin/test1
<build_dir>/lib/libfoo.so
But instead they are organized like this :
<build_dir>/src/test1
<build_dir>/tests/libfoo.so
What am I doing wrong ?
Thanks in advance,

Answer 1

You are giving instructions for the install step/build target, which is independent from the build tree under <binary_dir>.
Set CMAKE_INSTALL_PREFIX to a folder of your choice and run make install (assuming make build system here) after your build. The you will find CMAKE_INSTALL_PREFIX/lib/libfoo.so and CMAKE_INSTALL_PREFIX/bin/test1 as you told cmake. The DESTINATION path is always relative to CMAKE_INSTALL_PREFIX (unless you specify an absolute path, of course).
The compiled libs and binaries within the build tree (i.e. <build_dir>) will always reflect the source tree structure with respect to location; this cannot be changed and is not the intended way of use.
Generally there are three different "things": Source/Build/Install trees. The build tree mirrors the source tree structure and contains cmake-generated extra files and objects. The install "tree" is a setting of your choice, where CMAKE_INSTALL_PREFIX is the root directory under which libraries, archives and binaries are placed. You can control the behaviour completely (what you already intend to do!), although there are reasonable default settings.