Cargo build failed: could not find macro `llvm_asm` in this scope

Question

I am trying to build rust-fractal-gui but the build always fails with these errors:

$ cargo build --release

...

Compiling parking_lot v0.11.2
error: cannot find macro `llvm_asm` in this scope
  --> /home/riley/.cargo/registry/src/github.com-1ecc6299db9ec823/parking_lot-0.11.2/src/elision.rs:77:13
   |
77 |             llvm_asm!("xacquire; lock; cmpxchgq $2, $1"
   |             ^^^^^^^^

error: cannot find macro `llvm_asm` in this scope
   --> /home/riley/.cargo/registry/src/github.com-1ecc6299db9ec823/parking_lot-0.11.2/src/elision.rs:108:13
    |
108 |             llvm_asm!("xrelease; lock; xaddq $2, $1"
    |             ^^^^^^^^

error[E0635]: unknown feature `llvm_asm`
  --> /home/riley/.cargo/registry/src/github.com-1ecc6299db9ec823/parking_lot-0.11.2/src/lib.rs:14:42
   |
14 | #![cfg_attr(feature = "nightly", feature(llvm_asm))]
   |                                          ^^^^^^^^

For more information about this error, try `rustc --explain E0635`.
error: could not compile `parking_lot` due to 3 previous errors
warning: build failed, waiting for other jobs to finish...

Ouput of rustup show:

rustup home:  /home/riley/.rustup

installed toolchains
--------------------

stable-x86_64-unknown-linux-gnu (default)
nightly-x86_64-unknown-linux-gnu
1.48.0-x86_64-unknown-linux-gnu

active toolchain
----------------

nightly-x86_64-unknown-linux-gnu (directory override for '/home/riley/projects/rust-fractal-gui')
rustc 1.64.0-nightly (c2f428d2f 2022-07-14)

I have updated my nightly toolchain to the latest version with rustup update nightly and then rustup override set nightly see this issue but it did not take care of the problem.

Answer 1

Since rustc-nightly-2022-01-17 the macro llvm_asm! was removed in favor of the new asm! macro. rust-fractal-gui was using an outdated version of parking_lot which still used the llvm_asm! macro, causing this error. A PR has since been merged which fixes the issue.