how to generate compile_commands.json? about gccrs

[dkm]

There's no unique way to do that. The most common one is to use bear during the compiler build.
The bare command would be:

$ cd build
$ bear -- make

then you have the compile_commands.json. But this also includes all libs & tools. You may want to only do that for the compiler:

$ cd build
$ bear -- make all-gcc

And if you're lucky, you can even use -j XX to have a parallel build, but for many people (me included) it doesn't work and bear hangs during the link).

I'll close this "issue", as it's not really an issue. If you have question, you should come in our zulip. This topic has been discussed several times already, see https://gcc-rust.zulipchat.com/#narrow/stream/266906-new-members/topic/Starting.20out/near/412903500 for example :)