pub fn rustc_version() -> Result<String, String>Expand description
The rustc version the artifact would compile under: $RUSTC when
set (the pinned-toolchain convention every build script here
follows), rustc otherwise. The version string is the input, not
a parsed triple — rustc --version is what a human compares.
§Errors
If rustc cannot be run: an artifact address computed without knowing the compiler would silently collide across toolchains.