From: David Blaikie <dblaikie@gmail.com>
Date: Wed, 24 Oct 2012 21:29:06 +0000 (+0000)
Subject: Fix false positive in -Wunused-variable when a ctor call make involve cleanups.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=39e177692ea2096af2ad0dcead79250b50958fa3;p=clang

Fix false positive in -Wunused-variable when a ctor call make involve cleanups.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@166625 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 19442b98c1..e8d017c098 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -1286,6 +1286,8 @@ static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) {
           return false;
 
         if (const Expr *Init = VD->getInit()) {
+          if (const ExprWithCleanups *Cleanups = dyn_cast<ExprWithCleanups>(Init))
+            Init = Cleanups->getSubExpr();
           const CXXConstructExpr *Construct =
             dyn_cast<CXXConstructExpr>(Init);
           if (Construct && !Construct->isElidable()) {
diff --git a/test/SemaCXX/warn-unused-variables.cpp b/test/SemaCXX/warn-unused-variables.cpp
index 8bf2560417..4e8d51d319 100644
--- a/test/SemaCXX/warn-unused-variables.cpp
+++ b/test/SemaCXX/warn-unused-variables.cpp
@@ -123,3 +123,15 @@ namespace PR11550 {
     S3 z = a; // expected-warning {{unused variable 'z'}}
   }
 }
+
+namespace ctor_with_cleanups {
+  struct S1 {
+    ~S1();
+  };
+  struct S2 {
+    S2(const S1&);
+  };
+  void func() {
+    S2 s((S1()));
+  }
+}