A long time ago I was researching Compile Time Hashes (crc). I created this Perl script to generate a header file that contains the compile time Hash code.
Download GenConstHash.pl
The commands are pretty simple with a few options to match your style. One important thing to note is that it reuses the target file if it exists. There is a default hash function but if you can change it and the Perl script will make sure to keep it. Keep the function to one line however. There's also some gotchyas with modifying the function, see the full article for details.
Here's an example header file that only uses a string depth of 4 characters: