Merge pull request #1829 from xfxyjwf/fixcpp

Fix sign-comparison warnings and add a test for that.

src/Makefile.am

@@ -19,8 +19,9 @@ PTHREAD_DEF =
 endif
 
 if GCC
-# These are good warnings to turn on by default
-NO_OPT_CXXFLAGS = $(PTHREAD_CFLAGS) $(PTHREAD_DEF) $(ZLIB_DEF) -Wall -Wwrite-strings -Woverloaded-virtual -Wno-sign-compare
+# Turn on all warnings except for sign comparison (we ignore sign comparison
+# in Google so our code base have tons of such warnings).
+NO_OPT_CXXFLAGS = $(PTHREAD_CFLAGS) $(PTHREAD_DEF) $(ZLIB_DEF) -Wall -Wno-sign-compare
 else
 NO_OPT_CXXFLAGS = $(PTHREAD_CFLAGS) $(PTHREAD_DEF) $(ZLIB_DEF)
 endif
@@ -50,7 +51,8 @@ clean-local:
 	rm -f *.loT
 
 CLEANFILES = $(protoc_outputs) unittest_proto_middleman \
-             testzip.jar testzip.list testzip.proto testzip.zip
+             testzip.jar testzip.list testzip.proto testzip.zip \
+             no_warning_test.cc
 
 MAINTAINERCLEANFILES =   \
   Makefile.in
@@ -122,7 +124,6 @@ nobase_include_HEADERS =                                        \
   google/protobuf/reflection.h                                  \
   google/protobuf/reflection_ops.h                              \
   google/protobuf/repeated_field.h                              \
-  google/protobuf/repeated_field_reflection.h                   \
   google/protobuf/service.h                                     \
   google/protobuf/source_context.pb.h                           \
   google/protobuf/struct.pb.h                                   \
@@ -680,7 +681,7 @@ COMMON_TEST_SOURCES =                                          \
 
 check_PROGRAMS = protoc protobuf-test protobuf-lazy-descriptor-test \
                  protobuf-lite-test test_plugin protobuf-lite-arena-test \
-                 $(GZCHECKPROGRAMS)
+                 no-warning-test $(GZCHECKPROGRAMS)
 protobuf_test_LDADD = $(PTHREAD_LIBS) libprotobuf.la libprotoc.la \
                       ../gmock/gtest/lib/libgtest.la              \
                       ../gmock/lib/libgmock.la                    \
@@ -833,6 +834,27 @@ zcgunzip_LDADD = $(PTHREAD_LIBS) libprotobuf.la
 zcgunzip_SOURCES = google/protobuf/testing/zcgunzip.cc
 endif
 
+# This test target is to ensure all our public header files and generated
+# code is free from warnings. We have to be more pedantic about these
+# files because they are compiled by users with different compiler flags.
+no_warning_test.cc:
+	echo "// Generated from Makefile.am" > no_warning_test.cc
+	for FILE in $(nobase_include_HEADERS); do \
+	  if ! echo $${FILE} | grep "atomicops"; then \
+	    echo "#include <$${FILE}>" >> no_warning_test.cc; \
+	  fi \
+	done
+	echo "#include <gtest/gtest.h>" >> no_warning_test.cc
+	echo "TEST(NoWarningTest, Empty) {}" >> no_warning_test.cc
+
+no_warning_test_LDADD = $(PTHREAD_LIBS) libprotobuf.la      \
+                        ../gmock/gtest/lib/libgtest.la      \
+                        ../gmock/gtest/lib/libgtest_main.la
+no_warning_test_CPPFLAGS = -I$(srcdir)/../gmock/gtest/include
+no_warning_test_CXXFLAGS = $(PTHREAD_CFLAGS) $(PTHREAD_DEF) $(ZLIB_DEF) \
+                           -Wall -Werror
+nodist_no_warning_test_SOURCES = no_warning_test.cc $(protoc_outputs)
+
 TESTS = protobuf-test protobuf-lazy-descriptor-test protobuf-lite-test \
         google/protobuf/compiler/zip_output_unittest.sh $(GZTESTS)     \
-        protobuf-lite-arena-test
+        protobuf-lite-arena-test no-warning-test

src/google/protobuf/map.h

@@ -1250,7 +1250,7 @@ class Map {
     // Return whether table_[b] is a linked list that seems awfully long.
     // Requires table_[b] to point to a non-empty linked list.
     bool TableEntryIsTooLong(size_type b) {
-      const int kMaxLength = 8;
+      const size_type kMaxLength = 8;
       size_type count = 0;
       Node* node = static_cast<Node*>(table_[b]);
       do {

src/google/protobuf/wire_format_lite_inl.h

@@ -346,9 +346,9 @@ inline bool WireFormatLite::ReadPackedFixedSizePrimitive(
     io::CodedInputStream* input, RepeatedField<CType>* values) {
   int length;
   if (!input->ReadVarintSizeAsInt(&length)) return false;
-  const uint32 old_entries = values->size();
-  const uint32 new_entries = length / sizeof(CType);
-  const uint32 new_bytes = new_entries * sizeof(CType);
+  const int old_entries = values->size();
+  const int new_entries = length / sizeof(CType);
+  const int new_bytes = new_entries * sizeof(CType);
   if (new_bytes != length) return false;
   // We would *like* to pre-allocate the buffer to write into (for
   // speed), but *must* avoid performing a very large allocation due
@@ -382,7 +382,7 @@ inline bool WireFormatLite::ReadPackedFixedSizePrimitive(
 #else
     values->Reserve(old_entries + new_entries);
     CType value;
-    for (uint32 i = 0; i < new_entries; ++i) {
+    for (int i = 0; i < new_entries; ++i) {
       if (!ReadPrimitive<CType, DeclaredType>(input, &value)) return false;
       values->AddAlreadyReserved(value);
     }
@@ -392,7 +392,7 @@ inline bool WireFormatLite::ReadPackedFixedSizePrimitive(
     // safely allocate.  We read as much as we can into *values
     // without pre-allocating "length" bytes.
     CType value;
-    for (uint32 i = 0; i < new_entries; ++i) {
+    for (int i = 0; i < new_entries; ++i) {
       if (!ReadPrimitive<CType, DeclaredType>(input, &value)) return false;
       values->Add(value);
     }