
Referencing modulesPath in NixOS configurations can cause evaluation errors in restricted mode. If used as `${modulesPath}` (as in all use-sites in nixpkgs) the modules subtree is copied into its own store path. Access to this path will be forbidden in restricted mode. Converting to a string solves this issue. `${builtins.toString modulesPath}` will point to a subdirectory of the nixpkgs tree out of which evalModules is called. This change converts modulesPath to a string by default so that the call-site doesn't have to anymore.
*** NixOS *** NixOS is a Linux distribution based on the purely functional package management system Nix. More information can be found at http://nixos.org/nixos and in the manual in doc/manual.