//! When you execute `x.py build`, the steps executed are:
//!
//! * First, the python script is run. This will automatically download the
-//! stage0 rustc and cargo according to `src/stage0.txt`, or use the cached
+//! stage0 rustc and cargo according to `src/stage0.json`, or use the cached
//! versions if they're available. These are then used to compile rustbuild
//! itself (using Cargo). Finally, control is then transferred to rustbuild.
//!
{
eprintln!(
"
-Couldn't find required command: ninja
-You should install ninja, or set `ninja=false` in config.toml in the `[llvm]` section.
+Couldn't find required command: ninja (or ninja-build)
+
+You should install ninja as described at
+<https://github.com/ninja-build/ninja/wiki/Pre-built-Ninja-packages>,
+or set `ninja = false` in the `[llvm]` section of `config.toml`.
+Alternatively, set `download-ci-llvm = true` in that `[llvm]` section
+to download LLVM rather than building it.
"
);
std::process::exit(1);