Building a library using autotools from cmake

Question

This is my first try with cmake and I would like to have, if possible, some feedbacks about what I did since some problems remain.

In the CMakeLists.txt of the library folder, I created two makefile targets: configure-antlr3c and antlr3c. The first target runs the autotools configuration shell script, the second one runs the make executable to build the library:

# CMakeLists.txt in libantlr3c-3.1.3  add_custom_target(   configure-antlr3c   ${SHELL_EXECUTABLE} configure   WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR} )  add_custom_target(   antlr3c    ${MAKE}    DEPENDS configure-antlr3c    WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR} ) 

The main problem is thatconfigure-antlr3c target is always "out of date", so it will always be executed even if no changes happened. Moreover, I necessarily need to generate my cmake makefiles in a separate directory (not in the root directory of my project) to avoid overriding the autotools Makefile of the library...

Has anyone had this problem (building autotools projects with cmake) ? And if so, what have been your solutions ?

Thank you.

EDIT : Solution In the root CMakeLists.txt:

include(ExternalProject) ExternalProject_Add(   libantlr3c   SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/lib/libantlr3c-3.1.3   CONFIGURE_COMMAND ${CMAKE_CURRENT_SOURCE_DIR}/lib/libantlr3c-3.1.3/configure --prefix=${CMAKE_CURRENT_SOURCE_DIR}/lib/libantlr3c-3.1.3   PREFIX ${CMAKE_CURRENT_SOURCE_DIR}/lib/libantlr3c-3.1.3   BUILD_COMMAND make   BUILD_IN_SOURCE 1 ) 

Answer 1

I think that you'd be better off using the ExternalProject feature of cmake. I guess you have your project and have libantrl in a sub directory?

project       +- libantlr       +- mysrc   ---- etc ---- 

If that's the case, you can do something like this in the top level CMakeLists.txt:

cmake_minimum_required(VERSION 2.8) project(test) include(ExternalProject) ExternalProject_Add(libantlr     SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/libantlr     CONFIGURE_COMMAND ${CMAKE_CURRENT_SOURCE_DIR}/libantlr/configure --prefix=<INSTALL_DIR>     BUILD_COMMAND ${MAKE}) 

The <INSTALL_DIR> is expanded to something like libantlr-prefix, so things are installed in your build tree rather than in /usr/local, which is what autotools would do without a prefix.