From d57f52ca4d0e9d5d42dd6947d1e66d693625cf2c Mon Sep 17 00:00:00 2001
From: Douglas Gregor <dgregor@apple.com>
Date: Wed, 16 May 2012 17:01:33 +0000
Subject: [PATCH] Clean up r156925, so that we only mark the capturing
 DeclRefExpr of a lambda as referring to a local in an enclosing scope if
 we're in the enclosing scope of the lambda (not it's function call operator).
 Also, turn the test into an IR generation test, since that's where the
 crashes occurred. Really fixes PR12746 / <rdar://problem/11465120>.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@156926 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Sema/SemaExpr.cpp                         | 10 ++++---
 .../expr.prim.lambda/blocks-irgen.mm          | 29 +++++++++++++++++++
 .../expr/expr.prim/expr.prim.lambda/blocks.mm | 22 --------------
 3 files changed, 35 insertions(+), 26 deletions(-)
 create mode 100644 test/CXX/expr/expr.prim/expr.prim.lambda/blocks-irgen.mm

diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 440382bb5a..67b60fad51 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -10040,7 +10040,8 @@ diagnoseUncapturableValueReference(Sema &S, SourceLocation loc,
 static ExprResult captureInLambda(Sema &S, LambdaScopeInfo *LSI,
                                   VarDecl *Var, QualType FieldType, 
                                   QualType DeclRefType,
-                                  SourceLocation Loc) {
+                                  SourceLocation Loc,
+                                  bool RefersToEnclosingLocal) {
   CXXRecordDecl *Lambda = LSI->Lambda;
 
   // Build the non-static data member.
@@ -10069,8 +10070,8 @@ static ExprResult captureInLambda(Sema &S, LambdaScopeInfo *LSI,
   // C++ [expr.prim.labda]p12:
   //   An entity captured by a lambda-expression is odr-used (3.2) in
   //   the scope containing the lambda-expression.
-  Expr *Ref = new (S.Context) DeclRefExpr(Var, true, DeclRefType,
-                                          VK_LValue, Loc);
+  Expr *Ref = new (S.Context) DeclRefExpr(Var, RefersToEnclosingLocal, 
+                                          DeclRefType, VK_LValue, Loc);
   Var->setReferenced(true);
   Var->setUsed(true);
 
@@ -10413,7 +10414,8 @@ bool Sema::tryCaptureVariable(VarDecl *Var, SourceLocation Loc,
     Expr *CopyExpr = 0;
     if (BuildAndDiagnose) {
       ExprResult Result = captureInLambda(*this, LSI, Var, CaptureType,
-                                          DeclRefType, Loc);
+                                          DeclRefType, Loc,
+                                          I == N-1);
       if (!Result.isInvalid())
         CopyExpr = Result.take();
     }
diff --git a/test/CXX/expr/expr.prim/expr.prim.lambda/blocks-irgen.mm b/test/CXX/expr/expr.prim/expr.prim.lambda/blocks-irgen.mm
new file mode 100644
index 0000000000..9adecd0ee3
--- /dev/null
+++ b/test/CXX/expr/expr.prim/expr.prim.lambda/blocks-irgen.mm
@@ -0,0 +1,29 @@
+// RUN: %clang_cc1 -std=c++11 -fblocks -emit-llvm -o - -triple x86_64-apple-darwin11.3 %s | FileCheck %s
+
+namespace PR12746 {
+  // CHECK: define zeroext i1 @_ZN7PR127462f1EPi
+  bool f1(int *x) {
+    // CHECK: store i8* bitcast (i1 (i8*)* @__f1_block_invoke_0 to i8*)
+    bool (^outer)() = ^ {
+      auto inner = [&]() -> bool {
+	return x == 0;
+      };
+      return inner();
+    };
+    return outer();
+  }
+
+  // CHECK: define internal zeroext i1 @__f1_block_invoke_0
+  // CHECK: call zeroext i1 @"_ZNK7PR127462f119__f1_block_invoke_03$_0clEv"
+
+  bool f2(int *x) {
+    auto outer = [&]() -> bool {
+      bool (^inner)() = ^ {
+	return x == 0;
+      };
+      return inner();
+    };
+    return outer();
+  }
+}
+
diff --git a/test/CXX/expr/expr.prim/expr.prim.lambda/blocks.mm b/test/CXX/expr/expr.prim/expr.prim.lambda/blocks.mm
index 941443a0d6..0c3fdb2d80 100644
--- a/test/CXX/expr/expr.prim/expr.prim.lambda/blocks.mm
+++ b/test/CXX/expr/expr.prim/expr.prim.lambda/blocks.mm
@@ -86,25 +86,3 @@ namespace overloading {
     int &ir = accept_lambda_conv([](int x) { return x + 1; });
   }
 }
-
-namespace PR12746 {
-  bool f1(int *x) {
-    bool (^outer)() = ^ {
-      auto inner = [&]() -> bool {
-	return x == 0;
-      };
-      return inner();
-    };
-    return outer();
-  }
-
-  bool f2(int *x) {
-    auto outer = [&]() -> bool {
-      bool (^inner)() = ^ {
-	return x == 0;
-      };
-      return inner();
-    };
-    return outer();
-  }
-}