--- /usr/share/cmake-2.8/Modules/FindPkgConfig.cmake.ORIG	2013-11-15 16:32:25.966579094 +0900
+++ /usr/share/cmake-2.8/Modules/FindPkgConfig.cmake	2013-11-15 17:36:43.565351752 +0900
@@ -118,7 +118,7 @@
 endmacro()
 
 # Invokes pkgconfig, cleans up the result and sets variables
-macro(_pkgconfig_invoke _pkglist _prefix _varname _regexp)
+macro(_pkgconfig_invoke _pkglist _is_required _prefix _varname _regexp)
   set(_pkgconfig_invoke_result)
 
   execute_process(
@@ -127,8 +127,12 @@
     RESULT_VARIABLE _pkgconfig_failed)
 
   if (_pkgconfig_failed)
-    set(_pkgconfig_${_varname} "")
-    _pkgconfig_unset(${_prefix}_${_varname})
+    if (${_is_required})
+      message(FATAL_ERROR "The following pkgconfig command failed: '${PKG_CONFIG_EXECUTABLE} ${ARGN} ${_pkglist}' failed")
+    else()
+      set(_pkgconfig_${_varname} "")
+      _pkgconfig_unset(${_prefix}_${_varname})
+    endif()
   else()
     string(REGEX REPLACE "[\r\n]"                  " " _pkgconfig_invoke_result "${_pkgconfig_invoke_result}")
     string(REGEX REPLACE " +$"                     ""  _pkgconfig_invoke_result "${_pkgconfig_invoke_result}")
@@ -147,9 +151,9 @@
 
 # Invokes pkgconfig two times; once without '--static' and once with
 # '--static'
-macro(_pkgconfig_invoke_dyn _pkglist _prefix _varname cleanup_regexp)
-  _pkgconfig_invoke("${_pkglist}" ${_prefix}        ${_varname} "${cleanup_regexp}" ${ARGN})
-  _pkgconfig_invoke("${_pkglist}" ${_prefix} STATIC_${_varname} "${cleanup_regexp}" --static  ${ARGN})
+macro(_pkgconfig_invoke_dyn _pkglist _is_required _prefix _varname cleanup_regexp)
+  _pkgconfig_invoke("${_pkglist}" ${_is_required} ${_prefix}        ${_varname} "${cleanup_regexp}" ${ARGN})
+  _pkgconfig_invoke("${_pkglist}" ${_is_required} ${_prefix} STATIC_${_varname} "${cleanup_regexp}" --static  ${ARGN})
 endmacro()
 
 # Splits given arguments into options and a package list
@@ -294,10 +298,10 @@
           set(_pkg_check_prefix "${_prefix}_${_pkg_check_modules_pkg}")
         endif()
 
-        _pkgconfig_invoke(${_pkg_check_modules_pkg} "${_pkg_check_prefix}" VERSION    ""   --modversion )
-        _pkgconfig_invoke(${_pkg_check_modules_pkg} "${_pkg_check_prefix}" PREFIX     ""   --variable=prefix )
-        _pkgconfig_invoke(${_pkg_check_modules_pkg} "${_pkg_check_prefix}" INCLUDEDIR ""   --variable=includedir )
-        _pkgconfig_invoke(${_pkg_check_modules_pkg} "${_pkg_check_prefix}" LIBDIR     ""   --variable=libdir )
+        _pkgconfig_invoke(${_pkg_check_modules_pkg} ${_is_required} "${_pkg_check_prefix}" VERSION    ""   --modversion )
+        _pkgconfig_invoke(${_pkg_check_modules_pkg} ${_is_required} "${_pkg_check_prefix}" PREFIX     ""   --variable=prefix )
+        _pkgconfig_invoke(${_pkg_check_modules_pkg} ${_is_required} "${_pkg_check_prefix}" INCLUDEDIR ""   --variable=includedir )
+        _pkgconfig_invoke(${_pkg_check_modules_pkg} ${_is_required} "${_pkg_check_prefix}" LIBDIR     ""   --variable=libdir )
 
         if (NOT ${_is_silent})
           message(STATUS "  found ${_pkg_check_modules_pkg}, version ${_pkgconfig_VERSION}")
@@ -305,14 +309,14 @@
       endforeach()
 
       # set variables which are combined for multiple modules
-      _pkgconfig_invoke_dyn("${_pkg_check_modules_packages}" "${_prefix}" LIBRARIES           "(^| )-l" --libs-only-l )
-      _pkgconfig_invoke_dyn("${_pkg_check_modules_packages}" "${_prefix}" LIBRARY_DIRS        "(^| )-L" --libs-only-L )
-      _pkgconfig_invoke_dyn("${_pkg_check_modules_packages}" "${_prefix}" LDFLAGS             ""        --libs )
-      _pkgconfig_invoke_dyn("${_pkg_check_modules_packages}" "${_prefix}" LDFLAGS_OTHER       ""        --libs-only-other )
-
-      _pkgconfig_invoke_dyn("${_pkg_check_modules_packages}" "${_prefix}" INCLUDE_DIRS        "(^| )-I" --cflags-only-I )
-      _pkgconfig_invoke_dyn("${_pkg_check_modules_packages}" "${_prefix}" CFLAGS              ""        --cflags )
-      _pkgconfig_invoke_dyn("${_pkg_check_modules_packages}" "${_prefix}" CFLAGS_OTHER        ""        --cflags-only-other )
+      _pkgconfig_invoke_dyn("${_pkg_check_modules_packages}" ${_is_required} "${_prefix}" LIBRARIES           "(^| )-l" --libs-only-l )
+      _pkgconfig_invoke_dyn("${_pkg_check_modules_packages}" ${_is_required} "${_prefix}" LIBRARY_DIRS        "(^| )-L" --libs-only-L )
+      _pkgconfig_invoke_dyn("${_pkg_check_modules_packages}" ${_is_required} "${_prefix}" LDFLAGS             ""        --libs )
+      _pkgconfig_invoke_dyn("${_pkg_check_modules_packages}" ${_is_required} "${_prefix}" LDFLAGS_OTHER       ""        --libs-only-other )
+
+      _pkgconfig_invoke_dyn("${_pkg_check_modules_packages}" ${_is_required} "${_prefix}" INCLUDE_DIRS        "(^| )-I" --cflags-only-I )
+      _pkgconfig_invoke_dyn("${_pkg_check_modules_packages}" ${_is_required} "${_prefix}" CFLAGS              ""        --cflags )
+      _pkgconfig_invoke_dyn("${_pkg_check_modules_packages}" ${_is_required} "${_prefix}" CFLAGS_OTHER        ""        --cflags-only-other )
     endif()
   else()
     if (${_is_required})