cargo clippy + cargo check fail because of --emit asm

[ashleygwilliams]

ag-dubss-MacBook-Pro:boringtun ag_dubs$ cargo clippy
    Checking boringtun v0.2.0 (/Users/ag_dubs/CloudFlare/boringtun)
error: crate `base64` required to be available in rlib format, but was not found in this form

error: crate `hex` required to be available in rlib format, but was not found in this form

error: crate `libc` required to be available in rlib format, but was not found in this form

error: crate `ring` required to be available in rlib format, but was not found in this form

error: aborting due to 4 previous errors

error: Could not compile `boringtun`.

To learn more, run the command again with --verbose.

[ashleygwilliams]

this is a thing that cargo shouldn't fail on, but clippy uses cargo check and check does not like asm

i do not believe there is currently a way to ask cargo check to silently fail and let clippy lint so this blocks our usage of clippy.

[ashleygwilliams]

@vkrasnov can you tell me more about the motivation to the .cargo/config --emit asm? i'm a little surprised that it's faster.

[vkrasnov]

Me too, but it looks like vectorization doesn't happen when asm is not emitted. I can't really tell, need to look at objdump to see the difference in emitted machine code.

[ashleygwilliams]

so i definitely want us to have faster code, but i am a bit sad that this means that we can't enforce clippy on CLI and that contributors will run into a vaguely confusing error when they try to run cargo check or cargo clippy. at best i can document this in the README- but i'm still gonna see if i can ask around about conditionally applying --emit asm only to build and not check (not sure it's possible but we'll see!)

[hellow554]

Maybe worth opening an ticket in the rust repo?

[gawen]

As a work around during a development phase, I suggest to comment the following line to make cargo check works:

boringtun/.cargo/config

Line 4 in 37be474

"--emit", "asm", # For whatever reason rustc produces faster code when this flag is enabled

[jeff-hiner]

Closed by #223