Plrustc will not compile on alpine/postgres.

[therealjasonkenney]

I get this output when running the build script for plrustc:

3.516 + env 'RUSTFLAGS=-Clink-args=-Wl,-rpath,/usr/local/rustup/toolchains/1.70.0-x86_64-unknown-linux-musl/lib/rustlib/x86_64-unknown-linux-musl/lib -Zunstable-options -Zbinary-dep-depinfo' cargo build --release -p plrustc --bin plrustc --target x86_64-unknown-linux-musl
3.800     Updating crates.io index
4.751  Downloading crates ...
5.213   Downloaded once_cell v1.18.0
5.725   Downloaded libc v0.2.147
5.872    Compiling libc v0.2.147
5.872    Compiling once_cell v1.18.0
7.969    Compiling plrustc v1.2.3 (/tmp/plrust-1.2.3/plrustc/plrustc)
8.681 error: crate `rustc_ast` required to be available in rlib format, but was not found in this form
8.681

I looked in the library path, and indeed many rlibs are missing.

 FROM rust:alpine3.17 AS rust-builder

 RUN rustup update 1.70.0 \
    && rustup default 1.70.0 \
    && rustup component add --toolchain 1.70.0 llvm-tools-preview rustc-dev rust-src
  
  RUN wget -qO /tmp/plrust.tar.gz https://github.com/tcdi/plrust/archive/refs/tags/v1.2.3.tar.gz  \
    && tar -xvzf /tmp/plrust.tar.gz -C /tmp
  
  WORKDIR /tmp/plrust-1.2.3/plrustc
          
   RUN /bin/ash -x ./build.sh

pgrx, plrust both compile without errors. Just plrustc breaks.