Bug 518881: Make Send/Call*() methods for IPDL parent actors warn_unused_result. r=bent

ipc/ipdl/ipdl/cxx/ast.py

@@ -447,7 +447,7 @@ class FriendClassDecl(Node):
 
 class MethodDecl(Node):
     def __init__(self, name, params=[ ], ret=Type('void'),
-                 virtual=0, const=0, pure=0, static=0,
+                 virtual=0, const=0, pure=0, static=0, warn_unused=0,
                  typeop=None):
         assert not (virtual and static)
         assert not pure or virtual      # pure => virtual
@@ -467,6 +467,7 @@ class MethodDecl(Node):
         self.const = const              # bool
         self.pure = pure                # bool
         self.static = static            # bool
+        self.warn_unused = warn_unused  # bool
         self.typeop = typeop            # Type or None
 
     def __deepcopy__(self, memo):
@@ -474,7 +475,7 @@ class MethodDecl(Node):
             self.name,
             copy.deepcopy(self.params, memo),
             copy.deepcopy(self.ret, memo),
-            self.virtual, self.const, self.pure, self.static,
+            self.virtual, self.const, self.pure, self.static, self.warn_unused,
             copy.deepcopy(self.typeop, memo))
 
 class MethodDefn(Block):

ipc/ipdl/ipdl/cxx/cgen.py

@@ -216,6 +216,8 @@ class CxxCodeGen(CodePrinter, Visitor):
 
         if md.const:
             self.write(' const')
+        if md.warn_unused:
+            self.write(' NS_WARN_UNUSED_RESULT')
         if md.pure:
             self.write(' = 0')
 

ipc/ipdl/ipdl/lower.py

@@ -4202,6 +4202,7 @@ class _GenerateProtocolActorCode(ipdl.ast.Visitor):
             md.sendMethod().name,
             params=md.makeCxxParams(paramsems='in', returnsems='out',
                                     side=self.side, implicit=implicit),
+            warn_unused=(self.side == 'parent'),
             ret=Type.BOOL)
         if md.decl.type.isCtor():
             decl.ret = md.actorDecl().bareType(self.side)
@@ -4270,6 +4271,7 @@ class _ClassDeclDefn:
         md.decl.name = (clsname +'::'+ md.decl.name)
         md.decl.virtual = 0
         md.decl.static = 0
+        md.decl.warn_unused = 0
         for param in md.decl.params:
             if isinstance(param, Param):
                 param.default = None

xpcom/glue/Makefile.in

@@ -132,6 +132,7 @@ EXPORTS_mozilla = \
   Monitor.h \
   Mutex.h \
   SSE.h \
+  unused.h \
   $(NULL)
 
 SDK_LIBRARY     =                        \

xpcom/glue/objs.mk

@@ -79,6 +79,7 @@ XPCOM_GLUENS_SRC_LCPPSRCS =      \
   BlockingResourceBase.cpp       \
   DeadlockDetector.cpp           \
   SSE.cpp                        \
+  unused.cpp                     \
   nsAutoLock.cpp                 \
   nsGenericFactory.cpp           \
   nsProxyRelease.cpp             \

xpcom/glue/unused.cpp

@@ -0,0 +1,47 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: sw=2 ts=8 et :
+ */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (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.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is Mozilla Code.
+ *
+ * The Initial Developer of the Original Code is
+ *   The Mozilla Foundation
+ * Portions created by the Initial Developer are Copyright (C) 2010
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *   Chris Jones <jones.chris.g@gmail.com>
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#include "mozilla/unused.h"
+
+namespace mozilla {
+
+const unused_t unused = unused_t();
+
+}  // namespace mozilla

xpcom/glue/unused.h

@@ -0,0 +1,61 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: sw=2 ts=8 et :
+ */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (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.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is Mozilla Code.
+ *
+ * The Initial Developer of the Original Code is
+ *   The Mozilla Foundation
+ * Portions created by the Initial Developer are Copyright (C) 2010
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *   Chris Jones <jones.chris.g@gmail.com>
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#ifndef mozilla_unused_h
+#define mozilla_unused_h
+
+#include "nscore.h"
+
+namespace mozilla {
+
+//
+// Suppress GCC warnings about unused return values with
+//   unused << SomeFuncDeclaredWarnUnusedReturnValue();
+//
+struct NS_COM_GLUE unused_t { };
+
+extern const unused_t unused NS_COM_GLUE;
+
+template<typename T>
+inline void operator<<(const unused_t& /*unused*/, const T& /*unused*/) { }
+
+}
+
+#endif // mozilla_unused_h