Modernize CXXFLAGS on Unix and enable -Werror on CI.

Also clear up warnings that this exposed.

.github/workflows/ci-linux.yml

@@ -7,6 +7,7 @@ jobs:
     runs-on: ubuntu-20.04
     env:
       CXX: ${{ matrix.compiler }}
+      CXXFLAGS: -Werror
     steps:
       - uses: actions/checkout@v2
       - name: Install dependencies

CMakeLists.txt

@@ -188,19 +188,10 @@ if(MSVC)
 # Otherwise, we're not using Visual Studio
 else()
   # Set the compile flags to have all warnings on (including shadowed variables)
-  set(CXXFLAGS "${CXXFLAGS} -Wall -Wshadow")
-  # If on a *nix system, also set the compile flags to remove GNU extensions (favor ISO C++) as well as reject non-ISO C++ code, also remove all leading underscores in exported symbols (only on GNU compiler)
-  if(UNIX)
-    set(CXXFLAGS "${CXXFLAGS} -pedantic ${CMAKE_CXX_FLAGS}")
-    if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
-      set(CXXFLAGS "${CXXFLAGS} -fno-leading-underscore")
-    endif()
-  # If we aren't on a *nix system, we are using MinGW
-  else()
-    # Also, if we are building under MinGW, add another define for MinGW
-    if(MINGW)
-      add_definitions(-DMINGW)
-    endif()
+  set(CXXFLAGS "${CXXFLAGS} -Wall -Wextra -Wpedantic -Wno-unused-parameter ${CMAKE_CXX_FLAGS}")
+  # Also, if we are building under MinGW, add another define for MinGW
+  if(MINGW)
+    add_definitions(-DMINGW)
   endif()
 endif()
 

include/modules/httpd.h

@@ -28,6 +28,7 @@ struct HTTPReply
 	std::vector<cookie> cookies;
 
 	HTTPReply() = default;
+	HTTPReply& operator=(const HTTPReply &) = default;
 
 	HTTPReply(const HTTPReply& other) : error(other.error), length(other.length)
 	{
@@ -93,7 +94,7 @@ struct HTTPMessage
 class HTTPClient;
 class HTTPProvider;
 
-class HTTPPage : public Base
+class HTTPPage : public virtual Base
 {
 	Anope::string url;
 	Anope::string content_type;

include/regchannel.h

@@ -93,6 +93,7 @@ class CoreExport ChannelInfo : public Serializable, public Extensible
 	ChannelInfo(const ChannelInfo &ci);
 
 	~ChannelInfo();
+	ChannelInfo& operator=(const ChannelInfo &) = default;
 
 	void Serialize(Serialize::Data &data) const override;
 	static Serializable* Unserialize(Serializable *obj, Serialize::Data &);

modules/extra/m_mysql.cpp

@@ -151,7 +151,7 @@ class MySQLService : public Provider
 
 	Anope::string BuildQuery(const Query &q);
 
-	Anope::string FromUnixtime(time_t);
+	Anope::string FromUnixtime(time_t) override;
 };
 
 /** The SQL thread used to execute queries

modules/extra/m_sqlite.cpp

@@ -55,17 +55,17 @@ class SQLiteService : public Provider
 
 	void Run(Interface *i, const Query &query) override;
 
-	Result RunQuery(const Query &query);
+	Result RunQuery(const Query &query) override;
 
 	std::vector<Query> CreateTable(const Anope::string &table, const Data &data) override;
 
-	Query BuildInsert(const Anope::string &table, unsigned int id, Data &data);
+	Query BuildInsert(const Anope::string &table, unsigned int id, Data &data) override;
 
-	Query GetTables(const Anope::string &prefix);
+	Query GetTables(const Anope::string &prefix) override;
 
 	Anope::string BuildQuery(const Query &q);
 
-	Anope::string FromUnixtime(time_t);
+	Anope::string FromUnixtime(time_t) override;
 };
 
 class ModuleSQLite : public Module
@@ -200,7 +200,7 @@ Result SQLiteService::RunQuery(const Query &query)
 	if (err != SQLITE_DONE)
 		return SQLiteResult(query, real_query, sqlite3_errmsg(this->sql));
 
-	return result;
+	return std::move(result);
 }
 
 std::vector<Query> SQLiteService::CreateTable(const Anope::string &table, const Data &data)

modules/extra/stats/m_chanstats.cpp

@@ -639,13 +639,13 @@ class MChanstats : public Module
 		this->RunQuery(query);
 	}
 
-	void OnChanRegistered(ChannelInfo *ci)
+	void OnChanRegistered(ChannelInfo *ci) override
 	{
 		if (CSDefChanstats)
 			ci->Extend<bool>("CS_STATS");
 	}
 
-	void OnNickRegister(User *user, NickAlias *na, const Anope::string &)
+	void OnNickRegister(User *user, NickAlias *na, const Anope::string &) override
 	{
 		if (NSDefChanstats)
 			na->nc->Extend<bool>("NS_STATS");

src/siphash.cpp

@@ -120,12 +120,12 @@ uint64_t Anope::SipHash24(const void *src, unsigned long src_sz, const char key[
 	uint64_t t = 0; uint8_t *pt = (uint8_t *)&t; uint8_t *m = (uint8_t *)in;
 	switch (src_sz)
 	{
-		case 7: pt[6] = m[6];
-		case 6: pt[5] = m[5];
-		case 5: pt[4] = m[4];
+		case 7: pt[6] = m[6]; [[fallthrough]];
+		case 6: pt[5] = m[5]; [[fallthrough]];
+		case 5: pt[4] = m[4]; [[fallthrough]];
 		case 4: *((uint32_t*)&pt[0]) = *((uint32_t*)&m[0]); break;
-		case 3: pt[2] = m[2];
-		case 2: pt[1] = m[1];
+		case 3: pt[2] = m[2]; [[fallthrough]];
+		case 2: pt[1] = m[1]; [[fallthrough]];
 		case 1: pt[0] = m[0];
 	}
 	b |= _le64toh(t);

src/socketengines/socketengine_epoll.cpp

@@ -53,7 +53,7 @@ void SocketEngine::Change(Socket *s, bool set, SocketFlag flag)
 
 	memset(&ev, 0, sizeof(ev));
 
-	ev.events = (s->flags[SF_READABLE] ? EPOLLIN : 0) | (s->flags[SF_WRITABLE] ? EPOLLOUT : 0);
+	ev.events = (s->flags[SF_READABLE] ? EPOLLIN : 0u) | (s->flags[SF_WRITABLE] ? EPOLLOUT : 0u);
 	ev.data.fd = s->GetFD();
 
 	int mod;

src/sockets.cpp

@@ -306,7 +306,7 @@ bool cidr::match(const sockaddrs &other)
 	byte = len % 8;
 	if (byte)
 	{
-		uint8_t m = ~0 << (8 - byte);
+		uint8_t m = ~0u << (8 - byte);
 		return (*ip & m) == (*their_ip & m);
 	}