Fails to compile cssparser 0.25.9

[jyn514]

This is cg_clif built from rust-lang/rust#78624 using codegen-backends = ["cranelift"], so I think 8063c37.

$ git clone https://github.com/servo/rust-cssparser && cd rust-cssparser
$ git checkout v0.25.9
$ cargo +stage1 build
   Compiling cssparser v0.25.9 (/home/joshua/rust-cssparser)
   Compiling cssparser-macros v0.3.6 (/home/joshua/rust-cssparser/macros)
warning: Argument of type `proc_macro::bridge::buffer::Slice<u8>` with pass mode `ByValPair(types::I64, types::I64)` is not yet supported for non-rust abi `"C"`. Calling this function may result in a crash.
   --> /home/joshua/rustc/library/proc_macro/src/bridge/buffer.rs:134:9
    |
134 |         extern "C" fn extend_from_slice<T: Copy>(b: Buffer<T>, xs: Slice<'_, T>) -> Buffer<T> {
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

warning: 1 warning emitted

error: failed to run custom build command for `cssparser v0.25.9`

Caused by:
  process didn't exit successfully: `/home/joshua/.local/lib/cargo/target/debug/build/cssparser-a9d0987f2ba68887/build-script-build` (signal: 6, SIGABRT: process abort signal)
  --- stdout
  cargo:rustc-cfg=rustc_has_pr45225
  cargo:rustc-cfg=has_std__mem__MaybeUninit
  cargo:rerun-if-changed=/home/joshua/.local/lib/cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/cssparser-0.25.9/src/tokenizer.rs

  --- stderr
  fatal runtime error: failed to initiate panic, error 5

[bjorn3]

[...]
#8  0x0000555555966d9f in std::panicking::begin_panic (arg0=0x2, arg1=0x7ffff7d84510, arg2=0x0) at /home/bjorn/Documenten/cg_clif3/build_sysroot/sysroot_src/library/std/src/panicking.rs:521
#9  0x000055555599a5cb in proc_macro::bridge::client::<impl proc_macro::bridge::Bridge>::with::{{closure}} (sret0=0x2, arg1=0x7ffff7d84510)
    at sysroot_src/library/proc_macro/src/bridge/client.rs:331
[...]
#28 0x0000555555919956 in proc_macro2::detection::inside_proc_macro () at /home/bjorn/.cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/proc-macro2-1.0.13/src/detection.rs:15

It uses an outdated version of proc_macro2 that tries to detect if it is a proc macro by catching a panic. cg_clif doesn't support unwinding on panics.

[bjorn3]

Same issue as #1085.

[jyn514]

Ok, building docs.rs is blocked on cloudflare/lol-html#72 then.

[bjorn3]

This should be fixed now as of proc-macro 1.0.33.

[jyn514]

I just checked, docs.rs builds fine after updating the version of proc-macro in the lockfile :) thanks!