For 9ba1995060:

lib64 is not present under win32.

CPackCommonRules.cmake

@@ -13,9 +13,11 @@ SET (CPACK_PACKAGE_DESCRIPTION_FILE
 SET (pkgconfig_file "${PROJECT_BINARY_DIR}/pkg-config/${PROJECT_LOWERCASE_NAME}-${MAJOR}.pc")
 IF (EXISTS ${pkgconfig_file})
   SET (lib "lib")
-  IF("${CMAKE_SIZEOF_VOID_P}" EQUAL "8")
-    SET (lib "lib64")
-  ENDIF()
+  IF (UNIX)
+    IF("${CMAKE_SIZEOF_VOID_P}" EQUAL "8")
+      SET (lib "lib64")
+    ENDIF()
+  ENDIF(UNIX)
   INSTALL (FILES ${pkgconfig_file} DESTINATION ${lib}/pkgconfig)
 ENDIF ()
 #SET (CPACK_NSIS_PACKAGE_NAME "${PROJECT_NAME}")

PkgConfigCommonRules.cmake

@@ -5,9 +5,11 @@ ELSE (WIN32)
 ENDIF (WIN32)
 SET (PkgConfigExecPrefix "\${prefix}")
 SET (lib "lib")
-IF("${CMAKE_SIZEOF_VOID_P}" EQUAL "8")
-  SET (lib "lib64")
-ENDIF()
+IF(UNIX)
+  IF("${CMAKE_SIZEOF_VOID_P}" EQUAL "8")
+    SET (lib "lib64")
+  ENDIF()
+ENDIF(UNIX)
 SET (PkgConfigLibDir "\${exec_prefix}/${lib}")
 SET (PkgConfigIncludeDir "\${prefix}/include")
 

ValaLibCommonRules.cmake

@@ -43,9 +43,11 @@ IF (LibIsPlugin)
 ENDIF (LibIsPlugin)
 
 SET (lib "lib")
-IF("${CMAKE_SIZEOF_VOID_P}" EQUAL "8")
-  SET (lib "lib64")
-ENDIF()
+IF(UNIX)
+  IF("${CMAKE_SIZEOF_VOID_P}" EQUAL "8")
+    SET (lib "lib64")
+  ENDIF()
+ENDIF(UNIX)
 
 IF (UNIX)
   SET (install_dest ${lib}${install_prefix})