To avoid having to edit your configuration files too often, the compiler allows you to specify the following variables in the paths that you feed to the compiler:
To have these variables subsituted, just insert them with a $ prepended, as follows:
This is equivalent to
if the compiler version is 2.2.2 and the target OS is linux.
These replacements are valid on the command line and also in the configuration file.
On the linux command line, you must be careful to escape the $ since otherwise the shell will attempt to expand the variable for you, which may have undesired effects.