Illustrate update done to FindPythonQt.cmake while debugging Slicer packaging issue caused by CTK update. See here for more details: http://slicer-devel.65872.n3.nabble.com/Windows-and-Linux-nightly-packages-td4033451.html

FindPythonQt.cmake

# Find PythonQt
#
# Sets PYTHONQT_FOUND, PYTHONQT_INCLUDE_DIR, PYTHONQT_LIBRARY, PYTHONQT_LIBRARIES
#

# Python is required
find_package(PythonLibs)
if(NOT PYTHONLIBS_FOUND)
  message(FATAL_ERROR "error: Python is required to build PythonQt")
endif()

message("-------------------")
message("${CMAKE_CURRENT_LIST_FILE}:${CMAKE_CURRENT_LIST_LINE} - PYTHONQT_INSTALL_DIR:${PYTHONQT_INSTALL_DIR}")
get_property(cache_is_defined_PYTHONQT_INSTALL_DIR CACHE VALUE PROPERTY PYTHONQT_INSTALL_DIR DEFINED)
message("${CMAKE_CURRENT_LIST_FILE}:${CMAKE_CURRENT_LIST_LINE} - cache_is_defined_PYTHONQT_INSTALL_DIR:${cache_is_defined_PYTHONQT_INSTALL_DIR}")
get_property(cache_is_set_PYTHONQT_INSTALL_DIR CACHE VALUE PROPERTY PYTHONQT_INSTALL_DIR SET)
message("${CMAKE_CURRENT_LIST_FILE}:${CMAKE_CURRENT_LIST_LINE} - cache_is_set_PYTHONQT_INSTALL_DIR:${cache_is_set_PYTHONQT_INSTALL_DIR}")
get_property(cache_value_PYTHONQT_INSTALL_DIR CACHE VALUE PROPERTY PYTHONQT_INSTALL_DIR)
message("${CMAKE_CURRENT_LIST_FILE}:${CMAKE_CURRENT_LIST_LINE} - cache_value_PYTHONQT_INSTALL_DIR:${cache_value_PYTHONQT_INSTALL_DIR}")
#message("${CMAKE_CURRENT_LIST_FILE}:${CMAKE_CURRENT_LIST_LINE} - PYTHONQT_INCLUDE_DIR:${PYTHONQT_INCLUDE_DIR}")
#message("${CMAKE_CURRENT_LIST_FILE}:${CMAKE_CURRENT_LIST_LINE} - PYTHONQT_LIBRARY_RELEASE:${PYTHONQT_LIBRARY_RELEASE}")
#message("${CMAKE_CURRENT_LIST_FILE}:${CMAKE_CURRENT_LIST_LINE} - PYTHONQT_LIBRARY_DEBUG:${PYTHONQT_LIBRARY_DEBUG}")


#if(NOT EXISTS "${PYTHONQT_INSTALL_DIR}")
  find_path(PYTHONQT_INSTALL_DIR include/PythonQt/PythonQt.h DOC "Directory where PythonQt was installed.")
#endif()
find_path(PYTHONQT_INCLUDE_DIR PythonQt.h "${PYTHONQT_INSTALL_DIR}/include/PythonQt" DOC "Path to the PythonQt include directory")
find_library(PYTHONQT_LIBRARY_RELEASE PythonQt PATHS "${PYTHONQT_INSTALL_DIR}/lib" DOC "The PythonQt library.")
find_library(PYTHONQT_LIBRARY_DEBUG NAMES PythonQt${CTK_CMAKE_DEBUG_POSTFIX} PythonQt${CMAKE_DEBUG_POSTFIX} PythonQt PATHS "${PYTHONQT_INSTALL_DIR}/lib" DOC "The PythonQt library.")

message("-------------------")
message("${CMAKE_CURRENT_LIST_FILE}:${CMAKE_CURRENT_LIST_LINE} - PYTHONQT_INSTALL_DIR:${PYTHONQT_INSTALL_DIR}")
get_property(cache_is_defined_PYTHONQT_INSTALL_DIR CACHE VALUE PROPERTY PYTHONQT_INSTALL_DIR DEFINED)
message("${CMAKE_CURRENT_LIST_FILE}:${CMAKE_CURRENT_LIST_LINE} - cache_is_defined_PYTHONQT_INSTALL_DIR:${cache_is_defined_PYTHONQT_INSTALL_DIR}")
get_property(cache_is_set_PYTHONQT_INSTALL_DIR CACHE VALUE PROPERTY PYTHONQT_INSTALL_DIR SET)
message("${CMAKE_CURRENT_LIST_FILE}:${CMAKE_CURRENT_LIST_LINE} - cache_is_set_PYTHONQT_INSTALL_DIR:${cache_is_set_PYTHONQT_INSTALL_DIR}")
get_property(cache_value_PYTHONQT_INSTALL_DIR CACHE VALUE PROPERTY PYTHONQT_INSTALL_DIR)
message("${CMAKE_CURRENT_LIST_FILE}:${CMAKE_CURRENT_LIST_LINE} - cache_value_PYTHONQT_INSTALL_DIR:${cache_value_PYTHONQT_INSTALL_DIR}")
#message("${CMAKE_CURRENT_LIST_FILE}:${CMAKE_CURRENT_LIST_LINE} - PYTHONQT_INCLUDE_DIR:${PYTHONQT_INCLUDE_DIR}")
#message("${CMAKE_CURRENT_LIST_FILE}:${CMAKE_CURRENT_LIST_LINE} - PYTHONQT_LIBRARY_RELEASE:${PYTHONQT_LIBRARY_RELEASE}")
#message("${CMAKE_CURRENT_LIST_FILE}:${CMAKE_CURRENT_LIST_LINE} - PYTHONQT_LIBRARY_DEBUG:${PYTHONQT_LIBRARY_DEBUG}")

set(PYTHONQT_LIBRARY)
if(PYTHONQT_LIBRARY_RELEASE)
  list(APPEND PYTHONQT_LIBRARY optimized ${PYTHONQT_LIBRARY_RELEASE})
endif()
if(PYTHONQT_LIBRARY_DEBUG)
  list(APPEND PYTHONQT_LIBRARY debug ${PYTHONQT_LIBRARY_DEBUG})
endif()

mark_as_advanced(PYTHONQT_INSTALL_DIR)
mark_as_advanced(PYTHONQT_INCLUDE_DIR)
mark_as_advanced(PYTHONQT_LIBRARY_RELEASE)
mark_as_advanced(PYTHONQT_LIBRARY_DEBUG)

# On linux, also find libutil
if(UNIX AND NOT APPLE)
  find_library(PYTHONQT_LIBUTIL util)
  mark_as_advanced(PYTHONQT_LIBUTIL)
endif()

# All upper case _FOUND variable is maintained for backwards compatibility.
set(PYTHONQT_FOUND 0)
set(PythonQt_FOUND 0)
if(PYTHONQT_INCLUDE_DIR AND PYTHONQT_LIBRARY)
  # Currently CMake'ified PythonQt only supports building against a python Release build. 
  # This applies independently of CTK build type (Release, Debug, ...)
  add_definitions(-DPYTHONQT_USE_RELEASE_PYTHON_FALLBACK)
  set(PYTHONQT_FOUND 1)
  set(PythonQt_FOUND ${PYTHONQT_FOUND})
  set(PYTHONQT_LIBRARIES ${PYTHONQT_LIBRARY} ${PYTHONQT_LIBUTIL})
endif()