Auto merge of #120358 - tmandry:bump-fuchsia-8c-tests, r=Mark-Simulacrum

Bump Fuchsia, build tests, and use 8 core bots

- Build Fuchsia on 8 cores instead of 16
- Skip building cranelift for Fuchsia
- Bump Fuchsia (includes building tests)

This includes a change to the upstream build_fuchsia_from_rust_ci script that builds a minimal set of tests, to improve coverage on this builder. This would have caught rust-lang/rust-clippy#11952 and #119593.

See prior discussion on #119400 about building on 8 cores instead of 16. This PR combines changes from that and #119399, plus clean up.

r? `@Mark-Simulacrum`

.github/workflows/ci.yml

@@ -294,7 +294,7 @@ jobs:
           - name: x86_64-gnu-integration
             env:
               CI_ONLY_WHEN_CHANNEL: nightly
-            os: ubuntu-20.04-16core-64gb
+            os: ubuntu-20.04-8core-32gb
           - name: x86_64-gnu-debug
             os: ubuntu-20.04-8core-32gb
             env: {}

src/ci/docker/host-x86_64/x86_64-gnu-integration/Dockerfile

@@ -44,13 +44,17 @@ ENV CARGO_TARGET_X86_64_FUCHSIA_RUSTFLAGS \
 
 ENV TARGETS=x86_64-fuchsia
 ENV TARGETS=$TARGETS,x86_64-unknown-linux-gnu
+ENV TARGETS=$TARGETS,wasm32-unknown-unknown
 
 COPY scripts/sccache.sh /scripts/
 RUN sh /scripts/sccache.sh
 
 ENV RUST_INSTALL_DIR /checkout/obj/install
 RUN mkdir -p $RUST_INSTALL_DIR/etc
 
+# Fuchsia only supports LLVM.
+ENV CODEGEN_BACKENDS llvm
+
 ENV RUST_CONFIGURE_ARGS \
   --prefix=$RUST_INSTALL_DIR \
   --sysconfdir=etc \

src/ci/docker/host-x86_64/x86_64-gnu-integration/build-fuchsia.sh

@@ -5,7 +5,7 @@
 
 set -euf -o pipefail
 
-INTEGRATION_SHA=66793c4894bf6204579bbee3b79956335f31c768
+INTEGRATION_SHA=56310bca298872ffb5ea02e665956d9b6dc41171
 PICK_REFS=()
 
 checkout=fuchsia

src/ci/github-actions/ci.yml

@@ -478,7 +478,7 @@ jobs:
               # nightly features to compile, and this job would fail if
               # executed on beta and stable.
               CI_ONLY_WHEN_CHANNEL: nightly
-            <<: *job-linux-16c
+            <<: *job-linux-8c
 
           - name: x86_64-gnu-debug
             <<: *job-linux-8c

src/ci/run.sh

@@ -119,7 +119,8 @@ if [ "$DEPLOY$DEPLOY_ALT" = "1" ]; then
     RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set rust.verify-llvm-ir"
   fi
 
-  RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set rust.codegen-backends=${CODEGEN_BACKENDS:-llvm}"
+  CODEGEN_BACKENDS="${CODEGEN_BACKENDS:-llvm}"
+  RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set rust.codegen-backends=$CODEGEN_BACKENDS"
 else
   # We almost always want debug assertions enabled, but sometimes this takes too
   # long for too little benefit, so we just turn them off.
@@ -144,11 +145,12 @@ else
   # tests as it will fail them.
   if [[ "${ENABLE_GCC_CODEGEN}" == "1" ]]; then
     # Test the Cranelift and GCC backends in CI. Bootstrap knows which targets to run tests on.
-    RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set rust.codegen-backends=llvm,cranelift,gcc"
+    CODEGEN_BACKENDS="${CODEGEN_BACKENDS:-llvm,cranelift,gcc}"
   else
     # Test the Cranelift backend in CI. Bootstrap knows which targets to run tests on.
-    RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set rust.codegen-backends=llvm,cranelift"
+    CODEGEN_BACKENDS="${CODEGEN_BACKENDS:-llvm,cranelift}"
   fi
+  RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set rust.codegen-backends=$CODEGEN_BACKENDS"
 
   # We enable this for non-dist builders, since those aren't trying to produce
   # fresh binaries. We currently don't entirely support distributing a fresh