How to enable CFGs in rust-analyzer?

Hi. I want to set a cfg in VSCode so RA will check code under a cfg check. The cfg is histogram_readback . I see in the user manual for rust-analyzer User Manual there is rust-analyzer.cargo.cfgs which can be set to turn specific CFGs on or off. I have found that in my settings.json file.

The problem is that "rust-analyzer.cargo.cfgs" takes a JSON object, and I have no idea what the format is supposed to be.

"rust-analyzer.cargo.cfgs": {

doesn't work as you can't have a key without a value in JSON.

"rust-analyzer.cargo.cfgs": {
    "histogram_readback": true

doesn't work either.

1 Like

Did you try using an empty string as the value?

You could also use RUSTFLAGS to set the cfg if that doesn't work


This topic was automatically closed 90 days after the last reply. We invite you to open a new topic if you have further questions or comments.