From: Eli Friedman <eli.friedman@gmail.com>
Date: Mon, 24 Sep 2012 23:02:26 +0000 (+0000)
Subject: Handle C++ functional casts in a similar way to C-style casts in
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=6319917b5021e9602389b49ca4f245d235e9b90a;p=clang

Handle C++ functional casts in a similar way to C-style casts in
unused expression warnings.  <rdar://problem/12359208>.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@164569 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/AST/Expr.cpp b/lib/AST/Expr.cpp
index 74308a0093..30342585c8 100644
--- a/lib/AST/Expr.cpp
+++ b/lib/AST/Expr.cpp
@@ -2019,6 +2019,7 @@ bool Expr::isUnusedResultAWarning(const Expr *&WarnE, SourceLocation &Loc,
     R1 = getSourceRange();
     return true;
   }
+  case CXXFunctionalCastExprClass:
   case CStyleCastExprClass: {
     // Ignore an explicit cast to void unless the operand is a non-trivial
     // volatile lvalue.
diff --git a/test/SemaCXX/unused.cpp b/test/SemaCXX/unused.cpp
index 54898c828e..b9877a1ba4 100644
--- a/test/SemaCXX/unused.cpp
+++ b/test/SemaCXX/unused.cpp
@@ -34,3 +34,15 @@ namespace derefvolatile {
     (void)y; // don't warn here, because it's a common pattern.
   }
 }
+
+// <rdar://problem/12359208>
+namespace AnonObject {
+  struct Foo {
+    Foo(const char* const message);
+    ~Foo();
+  };
+  void f() {
+    Foo("Hello World!");  // don't warn
+    int(1); // expected-warning {{expression result unused}}
+  }
+}