From b91e6f6f40864d54903d707d7f19a9732188b670 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C4=99drzej=20Nowacki?= <jedrzej.nowacki@qt.io>
Date: Tue, 12 Mar 2019 09:22:15 +0100
Subject: [PATCH] Issue a warning about unused result of qScopeGuard and
 QScopeGuard
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If the result is unassigned then resulting QScopeGuard is destroyed
immediately, we can warn about it, as it is definitely a bug.

Change-Id: I627b05cecb3d0e62dbc24373e621f2be36d9b324
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
---
 src/corelib/tools/qscopeguard.h | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/corelib/tools/qscopeguard.h b/src/corelib/tools/qscopeguard.h
index 31100fcabb..0f61996eb6 100644
--- a/src/corelib/tools/qscopeguard.h
+++ b/src/corelib/tools/qscopeguard.h
@@ -50,7 +50,12 @@ template <typename F> class QScopeGuard;
 template <typename F> QScopeGuard<F> qScopeGuard(F f);
 
 template <typename F>
-class QScopeGuard
+class
+#ifndef __INTEL_COMPILER
+// error #2621: attribute "__warn_unused_result__" does not apply here
+Q_REQUIRED_RESULT
+#endif
+QScopeGuard
 {
 public:
     QScopeGuard(QScopeGuard &&other) Q_DECL_NOEXCEPT
@@ -86,6 +91,10 @@ private:
 
 
 template <typename F>
+#ifndef __INTEL_COMPILER
+// Causes "error #3058: GNU attributes on a template redeclaration have no effect"
+Q_REQUIRED_RESULT
+#endif
 QScopeGuard<F> qScopeGuard(F f)
 {
     return QScopeGuard<F>(std::move(f));