CI: Add code coverage mesurement for powerpc-unknown-linux-gnu.

Profiler builtins were added in
rust-lang/rust#119404.

.github/workflows/ci.yml

@@ -529,7 +529,7 @@ jobs:
           - i686-unknown-linux-gnu         # Has assembly
           # TODO: arm-unknown-linux-gnueabi # Has assembly but doesn't build w/ clang
           # TODO: armv7-unknown-linux-gnueabihf # Has assembly but doesn't have profiler builtins
-          # TODO: powerpc-unknown-linux-gnu  No assembly 32-bit big-endian but doesn't have profiler builtins
+          - powerpc-unknown-linux-gnu      # No assembly 32-bit big-endian with flags
           - powerpc64-unknown-linux-gnu    # No assembly 64-bit big-endian with flags
           - powerpc64le-unknown-linux-gnu  # No assembly 64-bit little-endian with flags
           - riscv64gc-unknown-linux-gnu    # No assembly 64-bit little-endian without flags
@@ -573,6 +573,9 @@ jobs:
           - target: i686-unknown-linux-gnu
             host_os: ubuntu-22.04
 
+          - target: powerpc-unknown-linux-gnu
+            host_os: ubuntu-22.04
+
           - target: powerpc64-unknown-linux-gnu
             host_os: ubuntu-22.04
 

mk/cargo.sh

@@ -231,11 +231,18 @@ if [ -n "${RING_COVERAGE-}" ]; then
       ;;
   esac
 
+  additional_rustflags=""
+  case "$target" in
+    powerpc-unknown-linux-gnu)
+      additional_rustflags="-latomic"
+    ;;
+  esac
+
   runner_var=CARGO_TARGET_${target_upper}_RUNNER
   declare -x "${runner_var}=mk/runner ${!runner_var-}"
 
   rustflags_var=CARGO_TARGET_${target_upper}_RUSTFLAGS
-  declare -x "${rustflags_var}=-Cinstrument-coverage ${!rustflags_var-}"
+  declare -x "${rustflags_var}=${additional_rustflags} -Cinstrument-coverage ${!rustflags_var-}"
 fi
 
 if [ -n "${use_clang}" ]; then