Compiler/TMS320F28377D: Use Variables in file for --cmd_file option

Tool/software: TI C/C++ Compiler

Hi all

Im am using the compiler option --cmd_file to specify compiler options in a file. 

In this file i would like to specify several --include_path options.

These include paths should be relativ to the project path. Therefore i would like to use path variables. 

Compiler Flag:
--cmd_file="C:\Software\Project\Lib\trunk\Includes.txt"

Includes.txt:
--include_path="${PROJECT_ROOT}/Lib/trunk/Dir1"
--include_path="${PROJECT_ROOT}/Lib/trunk/Dir2"
--include_path="${PROJECT_ROOT}/Lib/trunk/Dir3"
--include_path="${PROJECT_ROOT}/Lib/trunk/Types"
--include_path="${PROJECT_ROOT}/Lib/trunk/Filter"
--include_path="${PROJECT_ROOT}/Lib/trunk/Version"

If the file contains the full paths, without using variable PROJECT_ROOT compiler runs properly.

With us of variabale the compiler creates error 
"..\Lib\trunk\Version\Version.h", line 29: fatal error #1965: cannot open source file "Types.h"

Anyone knows what the problem is? Any better idea to do that?

Thanks for your time.
Kind regards