cmake vs. opencv

[Ryan Schmidt]

> On Jun 12, 2012 (Tuesday), at 2:57 AM, Ryan Schmidt wrote:
> 
>> On Jun 11, 2012, at 14:05, Petr Vanek wrote:
>> 
>>> hi all,
>>> 
>>> I'm facing really strange issue. App I want to pack for macports uses cmake for building and OpenCV as a runtime/build dependency.
>>> 
>>> OpenCV is handled by pkg-config in CMakeLists.txt. But the OpenCV_LIBRARIES variable is always empty.
>>> 
>>> Here is a minimal example for CMakeLists.txt:
>>> ######
>>> CMAKE_MINIMUM_REQUIRED(VERSION 2.8.0)
>>> 
>>> project(test)
>>> 
>>> find_package(PkgConfig)
>>> 	
>>> pkg_check_modules(OpenCV opencv>=2.1.0)
>>> pkg_check_modules(Zlib zlib>=1.0)
>>> 
>>> get_cmake_property(_variableNames VARIABLES)
>>> foreach (_variableName ${_variableNames})
>>>  message(STATUS "${_variableName}=${${_variableName}}")
>>> endforeach()
>>> ######
>>> 
>>> The zlib is there for reference (correctly filled).
>>> So what can be wrong? Cmake or OpenCV pkg-config file?
>> 
>> Can you show us the Portfile you're working on?

Thanks for sending me the Portfile. I see the configure phase fails with this message:

> CMake Error at CMakeLists.txt:165 (find_package):
>   By not providing "FindOpenCV.cmake" in CMAKE_MODULE_PATH this project has
>   asked CMake to find a package configuration file provided by "OpenCV", but
>   CMake did not find one.
> 
>   Could not find a package configuration file provided by "OpenCV" (requested
>   version 2.1.0) with any of the following names:
> 
>     OpenCVConfig.cmake
>     opencv-config.cmake
> 
>   Add the installation prefix of "OpenCV" to CMAKE_PREFIX_PATH or set
>   "OpenCV_DIR" to a directory containing one of the above files.  If "OpenCV"
>   provides a separate development package or SDK, be sure it has been
>   installed.

So I used "port contents opencv" to discover that it installs the file /opt/local/lib/cmake/OpenCVConfig.cmake. Therefore I modified your Portfile and added "-DOpenCV_DIR=${prefix}/lib/cmake" to the configure.args. That allowed it to get through the configure phase, but it failed during the build phase with "error: #if with no expression".