ci: add cmake debug output and --parallel build option

Author: ryanofsky

ci/scripts/ci.sh

@@ -41,14 +41,20 @@ src_dir=$PWD
 mkdir -p "$CI_DIR"
 cd "$CI_DIR"
 git --no-pager log -1 || true
-cmake "$src_dir" "${CMAKE_ARGS[@]+"${CMAKE_ARGS[@]}"}"
+cmake_args=("${CMAKE_ARGS[@]+"${CMAKE_ARGS[@]}"}")
+if ! cmake "$src_dir" "${cmake_args[@]}"; then
+  # If cmake failed, try it again with debug options.
+  # Could add --trace / --trace-expand here too for more information but these are very verbose.
+  cmake_args+=(--debug-find --debug-trycompile --log-level=DEBUG)
+  cmake "$src_dir" "${cmake_args[@]}"
+fi
 if ver_ge "$cmake_ver" "3.15"; then
-  cmake --build . -t "${BUILD_TARGETS[@]}" -- "${BUILD_ARGS[@]+"${BUILD_ARGS[@]}"}"
+  cmake --build . --parallel -t "${BUILD_TARGETS[@]}" -- "${BUILD_ARGS[@]+"${BUILD_ARGS[@]}"}"
 else
   # Older versions of cmake can only build one target at a time with --target,
   # and do not support -t shortcut
   for t in "${BUILD_TARGETS[@]}"; do
-    cmake --build . --target "$t" -- "${BUILD_ARGS[@]+"${BUILD_ARGS[@]}"}"
+    cmake --build . --parallel --target "$t" -- "${BUILD_ARGS[@]+"${BUILD_ARGS[@]}"}"
   done
 fi
 ctest --output-on-failure