Make generated CMake files valid when install paths are absolute (aws#2630)

Author: jmklix

cmake/AWSSDKConfig.cmake

@@ -98,14 +98,18 @@ if (NOT AWSSDK_CORE_HEADER_FILE)
     message(FATAL_ERROR "AWS SDK for C++ is missing, please install it first")
 endif()
 
-# based on core header file path, inspects the actual AWSSDK_ROOT_DIR
-get_filename_component(AWSSDK_ROOT_DIR "${AWSSDK_CORE_HEADER_FILE}" PATH)
-get_filename_component(AWSSDK_ROOT_DIR "${AWSSDK_ROOT_DIR}" PATH)
-get_filename_component(AWSSDK_ROOT_DIR "${AWSSDK_ROOT_DIR}" PATH)
-get_filename_component(AWSSDK_ROOT_DIR "${AWSSDK_ROOT_DIR}" PATH)
-
-if (NOT AWSSDK_ROOT_DIR)
-    message(FATAL_ERROR "AWSSDK_ROOT_DIR is not set or can't be calculated from the path of core header file")
+if (IS_ABSOLUTE ${AWSSDK_INSTALL_LIBDIR})
+    set(AWSSDK_ROOT_DIR "")
+else()
+    # based on core header file path, inspects the actual AWSSDK_ROOT_DIR
+    get_filename_component(AWSSDK_ROOT_DIR "${AWSSDK_CORE_HEADER_FILE}" PATH)
+    get_filename_component(AWSSDK_ROOT_DIR "${AWSSDK_ROOT_DIR}" PATH)
+    get_filename_component(AWSSDK_ROOT_DIR "${AWSSDK_ROOT_DIR}" PATH)
+    get_filename_component(AWSSDK_ROOT_DIR "${AWSSDK_ROOT_DIR}" PATH)
+
+    if (NOT AWSSDK_ROOT_DIR)
+        message(FATAL_ERROR "AWSSDK_ROOT_DIR is not set or can't be calculated from the path of core header file")
+    endif()
 endif()
 
 

toolchains/pkg-config.pc.in

@@ -1,5 +1,5 @@
-includedir=@CMAKE_INSTALL_PREFIX@/@INCLUDE_DIRECTORY@
-libdir=@CMAKE_INSTALL_PREFIX@/@LIBRARY_DIRECTORY@
+includedir=@INCLUDE_DIRECTORY@
+libdir=@LIBRARY_DIRECTORY@
 
 Name: @PROJECT_NAME@
 Description: @PROJECT_DESCRIPTION@