Enable clang's warning about implicit fallthrough.

src/object-store/CMake/CompilerFlags.cmake

@@ -25,6 +25,7 @@ if(${CMAKE_CXX_COMPILER_ID} MATCHES "Clang")
         -Wmissing-prototypes
         -Wnewline-eof
         -Wshorten-64-to-32
+        -Wimplicit-fallthrough
     )
 endif()
 

src/object-store/src/CMakeLists.txt

@@ -40,6 +40,7 @@ set(HEADERS
     parser/parser.hpp
     parser/query_builder.hpp
     util/atomic_shared_ptr.hpp
+    util/compiler.hpp
     util/format.hpp
     util/thread_id.hpp
     util/thread_local.hpp)

src/object-store/src/parser/query_builder.cpp

@@ -21,6 +21,7 @@
 
 #include "object_store.hpp"
 #include "schema.hpp"
+#include "util/compiler.hpp"
 #include "util/format.hpp"
 
 #include <realm.hpp>
@@ -259,6 +260,7 @@ void add_link_constraint_to_query(realm::Query &query,
     switch (op) {
         case Predicate::Operator::NotEqual:
             query.Not();
+            REALM_FALLTHROUGH;
         case Predicate::Operator::Equal: {
             size_t col = prop_expr.prop->table_column;
             query.links_to(col, query.get_table()->get_link_target(col)->get(row_index));
@@ -464,8 +466,8 @@ void do_add_null_comparison_to_query<Link>(Query &query, Predicate::Operator op,
     precondition(expr.indexes.empty(), "KeyPath queries not supported for object comparisons.");
     switch (op) {
         case Predicate::Operator::NotEqual:
-            // for not equal we negate the query and then fallthrough
             query.Not();
+            REALM_FALLTHROUGH;
         case Predicate::Operator::Equal:
             query.and_query(query.get_table()->column<Link>(expr.prop->table_column).is_null());
             break;

src/object-store/src/results.cpp

@@ -23,23 +23,12 @@
 #include "object_schema.hpp"
 #include "object_store.hpp"
 #include "util/format.hpp"
+#include "util/compiler.hpp"
 
 #include <stdexcept>
 
 using namespace realm;
 
-#ifdef __has_cpp_attribute
-#define REALM_HAS_CCP_ATTRIBUTE(attr) __has_cpp_attribute(attr)
-#else
-#define REALM_HAS_CCP_ATTRIBUTE(attr) 0
-#endif
-
-#if REALM_HAS_CCP_ATTRIBUTE(clang::fallthrough)
-#define REALM_FALLTHROUGH [[clang::fallthrough]]
-#else
-#define REALM_FALLTHROUGH
-#endif
-
 Results::Results() = default;
 Results::~Results() = default;
 

src/object-store/src/util/compiler.hpp

@@ -0,0 +1,34 @@
+////////////////////////////////////////////////////////////////////////////
+//
+// Copyright 2015 Realm Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+////////////////////////////////////////////////////////////////////////////
+
+#ifndef REALM_UTIL_COMPILER_HPP
+#define REALM_UTIL_COMPILER_HPP
+
+#ifdef __has_cpp_attribute
+#define REALM_HAS_CCP_ATTRIBUTE(attr) __has_cpp_attribute(attr)
+#else
+#define REALM_HAS_CCP_ATTRIBUTE(attr) 0
+#endif
+
+#if REALM_HAS_CCP_ATTRIBUTE(clang::fallthrough)
+#define REALM_FALLTHROUGH [[clang::fallthrough]]
+#else
+#define REALM_FALLTHROUGH
+#endif
+
+#endif // REALM_UTIL_COMPILER_HPP