fix(ci): make LLVM backend opt-in to fix CI lint job

Change compiler default features from all-backends (which includes
llvm-backend) to cranelift-backend only. This prevents the lint job
from failing with "No suitable version of LLVM was found" since LLVM
is only installed in the dedicated llvm-backend CI lane.

Author: darmie

.github/workflows/ci.yml

@@ -28,7 +28,7 @@ jobs:
       - name: Check formatting
         run: cargo fmt --all -- --check
 
-      - name: Run clippy
+      - name: Run clippy (default features, no LLVM)
         run: cargo clippy --workspace --all-targets
 
   backend-feature-matrix:

crates/compiler/Cargo.toml

@@ -67,7 +67,7 @@ name = "simd_vectorization"
 harness = false
 
 [features]
-default = ["all-backends"]
+default = ["cranelift-backend"]
 cranelift-backend = ["cranelift", "cranelift-codegen", "cranelift-frontend", "cranelift-jit", "cranelift-module", "cranelift-native"]
 llvm-backend = ["inkwell"]
 all-backends = ["cranelift-backend", "llvm-backend"]