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authorMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
committerMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
commitad18d877ddd2a44d98fa12ccd3dbbcf4d0ac4299 (patch)
tree10027f336435511475e392454359edea8e25895d /mfbt/Unused.h
parent15477ed9af4859dacb069040b5d4de600803d3bc (diff)
downloaduxp-ad18d877ddd2a44d98fa12ccd3dbbcf4d0ac4299.tar.gz
Add m-esr52 at 52.6.0
Diffstat (limited to 'mfbt/Unused.h')
-rw-r--r--mfbt/Unused.h38
1 files changed, 38 insertions, 0 deletions
diff --git a/mfbt/Unused.h b/mfbt/Unused.h
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_unused_h
+#define mozilla_unused_h
+
+#include "mozilla/Types.h"
+
+#ifdef __cplusplus
+
+namespace mozilla {
+
+//
+// Suppress GCC warnings about unused return values with
+// Unused << SomeFuncDeclaredWarnUnusedReturnValue();
+//
+struct unused_t
+{
+ template<typename T>
+ inline void
+ operator<<(const T& /*unused*/) const {}
+};
+
+extern MFBT_DATA const unused_t Unused;
+
+} // namespace mozilla
+
+#endif // __cplusplus
+
+// An alternative to mozilla::Unused for use in (a) C code and (b) code where
+// linking with unused.o is difficult.
+#define MOZ_UNUSED(expr) \
+ do { if (expr) { (void)0; } } while (0)
+
+#endif // mozilla_unused_h