[do not merge] CI experiments

src/bootstrap/src/core/build_steps/compile.rs

@@ -1280,6 +1280,11 @@ pub fn rustc_cargo(
         ));
     }
 
+    if compiler.stage != 0 {
+        cargo.rustflag("-Cpanic=abort");
+        cargo.rustflag("-Cforce-unwind-tables=yes");
+    }
+
     rustc_cargo_env(builder, cargo, target, compiler.stage);
 }
 

src/bootstrap/src/core/build_steps/tool.rs

@@ -239,6 +239,19 @@ pub fn prepare_tool_cargo(
         }
     }
 
+    if compiler.stage != 0 {
+        if path.ends_with("rls")
+            || path.ends_with("clippy")
+            || path.ends_with("miri")
+            || path.ends_with("rustfmt")
+            || path.ends_with("rustdoc")
+            || path.ends_with("rustdoc-tool")
+        {
+            cargo.rustflag("-Cpanic=abort");
+            cargo.rustflag("-Cforce-unwind-tables=yes");
+        }
+    }
+
     // clippy tests need to know about the stage sysroot. Set them consistently while building to
     // avoid rebuilding when running tests.
     cargo.env("SYSROOT", builder.sysroot(compiler));

src/ci/github-actions/jobs.yml

@@ -121,7 +121,7 @@ pr:
 try:
   - name: dist-x86_64-linux
     env:
-      CODEGEN_BACKENDS: llvm,cranelift
+      CODEGEN_BACKENDS: llvm
     <<: *job-linux-16c
 
 # Main CI jobs that have to be green to merge a commit into master