Fix various build problems (#70)

Problems resolved are:

 - Ignoring a multiline comment in LLVM9
 - Adding return statements to methods where gcc cannot deduct
   that a case will always result in a return being executed.

Co-authored-by: Morten W. Jørgensen <Morten@comepile.it>

CMakeLists.txt

@@ -100,7 +100,7 @@ target_include_directories(hyde PUBLIC ${LLVM_INCLUDE_DIRS})
 target_include_directories(hyde PUBLIC ${PROJECT_SOURCE_DIR}/submodules/yaml-cpp/include/)
 target_include_directories(hyde PUBLIC ${PROJECT_SOURCE_DIR}/submodules/json/include/)
 
-target_compile_options(hyde PUBLIC -Wall -Werror -Wno-range-loop-analysis -DHYDE_FORCE_BOOST_FILESYSTEM=1)
+target_compile_options(hyde PUBLIC -Wall -Wno-comment -Werror -Wno-range-loop-analysis -DHYDE_FORCE_BOOST_FILESYSTEM=1)
 
 target_link_libraries(hyde
                       ${Boost_FILESYSTEM_LIBRARY}

emitters/yaml_base_emitter.cpp

@@ -87,6 +87,7 @@ hyde::json yaml_to_json(const YAML::Node& yaml) {
             throw std::runtime_error("YAML is not defined!");
         } break;
     }
+    return hyde::json();
 }
 
 /**************************************************************************************************/
@@ -132,6 +133,7 @@ YAML::Node json_to_yaml(const hyde::json& json) {
             throw std::runtime_error("Discarded JSON value");
         } break;
     }
+    return YAML::Node();
 }
 
 /**************************************************************************************************/

matchers/utilities.cpp

@@ -554,6 +554,8 @@ bool AccessCheck(ToolAccessFilter hyde_filter, clang::AccessSpecifier clang_acce
                     return false;
             }
     }
+
+    return false;
 }
 
 /**************************************************************************************************/

matchers/utilities.hpp

@@ -70,6 +70,7 @@ inline std::string to_string(clang::AccessSpecifier access) {
         case clang::AccessSpecifier::AS_none:
             return "none";
     }
+    return "unknown";
 }
 
 /**************************************************************************************************/