python x.py setup complains about missing ninja

[lopopolo]

Hi, I'm setting up a checkout of the Rust repository on a Windows machine. I would like to run x.py setup to generate a config.toml file with the library profile. x.py aborts due to ninja not being installed, even though this does not appear to be necessary for the library profile because x.py fetches pre-built copies of LLVM.

To work around this I had to copy the example config and manually modify the ninja setting to false. Running x.py setup again returns an error since the config file already exists, although it does suggest setting a top-level profile key.

This is a speedbump on the road to contributing.

[jyn514]

Note: to reproduce this, run x setup library (the error only occurs after the prompt for which profile).

[kornelski]

I've ran into this too. It'd be nice if setup could put ninja=false in config.toml automatically. Otherwise it's a funny situation where it requires config.toml in order to create the config.toml.

[kornelski]

The error message doesn't say in which section to put ninja=false in! Just ninja=false alone in the file causes a TOML parse error. I've tried putting it in a [build] section, but it didn't like it either.

[jyn514]

@kornelski it goes in the llvm section