Try to fix CI (#2918)

Fixes a few issues that have been cropping up:

* Update `rustup` on Windows to latest to skip over the 1.24.1 installed
  on GitHub Actions which can fail to install.
* Remove the no-longer-needed `define-llvm-env` action
* Install generic llvm/lldb packges instead of specific ones that may
  migrate in versions over time.

.github/actions/define-llvm-env/README.md

@@ -1,3 +0,0 @@
-# define-llvm-env
-
-Defines `DWARFDUMP` and `LLDB` path executable.

.github/actions/define-llvm-env/action.yml

@@ -1,6 +0,0 @@
-name: 'Set up a DWARFDUMP env'
-description: 'Set up a DWARFDUMP env (see tests/all/debug/dump.rs)'
-
-runs:
-  using: node12
-  main: 'main.js'

.github/actions/define-llvm-env/main.js

@@ -1,19 +0,0 @@
-#!/usr/bin/env node
-
-const fs = require('fs');
-
-function set_env(name, val) {
-  fs.appendFileSync(process.env['GITHUB_ENV'], `${name}=${val}\n`)
-}
-
-// On OSX pointing to brew's LLVM location.
-if (process.platform == 'darwin') {
-  set_env("DWARFDUMP", "/usr/local/opt/llvm/bin/llvm-dwarfdump");
-  set_env("LLDB", "/usr/local/opt/llvm/bin/lldb");
-}
-
-// On Linux pointing to specific version
-if (process.platform == 'linux') {
-  set_env("DWARFDUMP", "/usr/bin/llvm-dwarfdump-9");
-  set_env("LLDB", "/usr/bin/lldb-9");
-}

.github/actions/install-rust/main.js

@@ -6,11 +6,10 @@ function set_env(name, val) {
   fs.appendFileSync(process.env['GITHUB_ENV'], `${name}=${val}\n`)
 }
 
-if (process.platform === 'darwin') {
-  child_process.execSync(`curl https://sh.rustup.rs | sh -s -- -y --default-toolchain=none --profile=minimal`);
-  const bindir = `${process.env.HOME}/.cargo/bin`;
-  fs.appendFileSync(process.env['GITHUB_PATH'], `${bindir}\n`);
-  process.env.PATH = `${process.env.PATH}:${bindir}`;
+// Needed for now to get 1.24.2 which fixes a bug in 1.24.1 that causes issues
+// on Windows.
+if (process.platform === 'win32') {
+  child_process.execFileSync('rustup', ['self', 'update']);
 }
 
 child_process.execFileSync('rustup', ['set', 'profile', 'minimal']);

.github/workflows/main.yml

@@ -234,7 +234,6 @@ jobs:
     - uses: ./.github/actions/install-rust
       with:
         toolchain: ${{ matrix.rust }}
-    - uses: ./.github/actions/define-llvm-env
 
     - name: Install libclang
       # Note: libclang is pre-installed on the macOS and linux images.
@@ -277,21 +276,18 @@ jobs:
 
     # Test debug (DWARF) related functionality.
     - run: |
-        sudo apt-get update && sudo apt-get install -y gdb lldb
+        sudo apt-get update && sudo apt-get install -y gdb lldb llvm
         cargo test test_debug_dwarf -- --ignored --test-threads 1
       if: matrix.os == 'ubuntu-latest'
       env:
         RUST_BACKTRACE: 1
-        LLDB: /usr/bin/lldb
 
     # Test debug (DWARF) related functionality on new backend.
     - run: |
-        sudo apt-get update && sudo apt-get install -y gdb lldb
         cargo test test_debug_dwarf -- --ignored --test-threads 1 --test debug::
       if: matrix.os == 'ubuntu-latest'
       env:
         RUST_BACKTRACE: 1
-        LLDB: /usr/bin/lldb
 
     # Test uffd functionality on Linux
     - run: |
@@ -311,7 +307,7 @@ jobs:
         RUST_BACKTRACE: 1
 
   # Perform all tests (debug mode) for `wasmtime` with the old x86 backend.
-  test_x64:
+  test_x86:
     name: Test old x86 backend
     runs-on: ubuntu-latest
     steps:
@@ -321,7 +317,6 @@ jobs:
     - uses: ./.github/actions/install-rust
       with:
         toolchain: stable
-    - uses: ./.github/actions/define-llvm-env
 
     # Install wasm32 targets in order to build various tests throughout the
     # repo.