From 6d69e8c00bc1c5c06488e50823bd771c6fc02ced Mon Sep 17 00:00:00 2001
From: Richard Smith <richard-llvm@metafoo.co.uk>
Date: Tue, 28 Apr 2015 21:41:14 +0000
Subject: [PATCH] Fix assertion failure if a lambda array-capture is followed
 by a this capture.

llvm-svn: 236043
---
 clang/include/clang/Sema/ScopeInfo.h         | 10 ----------
 clang/lib/Sema/SemaLambda.cpp                |  7 ++++---
 clang/test/CodeGenCXX/lambda-expressions.cpp |  9 +++++++++
 3 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/clang/include/clang/Sema/ScopeInfo.h b/clang/include/clang/Sema/ScopeInfo.h
index 504fe87..15ee8a4 100644
--- a/clang/include/clang/Sema/ScopeInfo.h
+++ b/clang/include/clang/Sema/ScopeInfo.h
@@ -648,13 +648,6 @@ public:
   /// \brief Whether the lambda contains an unexpanded parameter pack.
   bool ContainsUnexpandedParameterPack;
 
-  /// \brief Variables used to index into by-copy array captures.
-  SmallVector<VarDecl *, 4> ArrayIndexVars;
-
-  /// \brief Offsets into the ArrayIndexVars array at which each capture starts
-  /// its list of array index variables.
-  SmallVector<unsigned, 4> ArrayIndexStarts;
-  
   /// \brief If this is a generic lambda, use this as the depth of 
   /// each 'auto' parameter, during initial AST construction.
   unsigned AutoTemplateParameterDepth;
@@ -842,9 +835,6 @@ CapturingScopeInfo::addThisCapture(bool isNested, SourceLocation Loc,
   Captures.push_back(Capture(Capture::ThisCapture, isNested, Loc, CaptureType,
                              Cpy));
   CXXThisCaptureIndex = Captures.size();
-
-  if (LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(this))
-    LSI->ArrayIndexStarts.push_back(LSI->ArrayIndexVars.size());
 }
 
 } // end namespace sema
diff --git a/clang/lib/Sema/SemaLambda.cpp b/clang/lib/Sema/SemaLambda.cpp
index fa67ded..8220641 100644
--- a/clang/lib/Sema/SemaLambda.cpp
+++ b/clang/lib/Sema/SemaLambda.cpp
@@ -818,7 +818,6 @@ VarDecl *Sema::createLambdaInitCaptureVarDecl(SourceLocation Loc,
   NewVD->markUsed(Context);
   NewVD->setInit(Init);
   return NewVD;
-
 }
 
 FieldDecl *Sema::buildInitCaptureField(LambdaScopeInfo *LSI, VarDecl *Var) {
@@ -1518,8 +1517,6 @@ ExprResult Sema::BuildLambdaExpr(SourceLocation StartLoc, SourceLocation EndLoc,
     ExplicitResultType = !LSI->HasImplicitReturnType;
     LambdaExprNeedsCleanups = LSI->ExprNeedsCleanups;
     ContainsUnexpandedParameterPack = LSI->ContainsUnexpandedParameterPack;
-    ArrayIndexVars.swap(LSI->ArrayIndexVars);
-    ArrayIndexStarts.swap(LSI->ArrayIndexStarts);
     
     CallOperator->setLexicalDeclContext(Class);
     Decl *TemplateOrNonTemplateCallOperatorDecl = 
@@ -1546,12 +1543,14 @@ ExprResult Sema::BuildLambdaExpr(SourceLocation StartLoc, SourceLocation EndLoc,
         CaptureInits.push_back(new (Context) CXXThisExpr(From.getLocation(),
                                                          getCurrentThisType(),
                                                          /*isImplicit=*/true));
+        ArrayIndexStarts.push_back(ArrayIndexVars.size());
         continue;
       }
       if (From.isVLATypeCapture()) {
         Captures.push_back(
             LambdaCapture(From.getLocation(), IsImplicit, LCK_VLAType));
         CaptureInits.push_back(nullptr);
+        ArrayIndexStarts.push_back(ArrayIndexVars.size());
         continue;
       }
 
@@ -1566,6 +1565,8 @@ ExprResult Sema::BuildLambdaExpr(SourceLocation StartLoc, SourceLocation EndLoc,
         if (InitResult.isInvalid())
           return ExprError();
         Init = InitResult.get();
+      } else {
+        ArrayIndexStarts.push_back(ArrayIndexVars.size());
       }
       CaptureInits.push_back(Init);
     }
diff --git a/clang/test/CodeGenCXX/lambda-expressions.cpp b/clang/test/CodeGenCXX/lambda-expressions.cpp
index 911f1ab..28a8841 100644
--- a/clang/test/CodeGenCXX/lambda-expressions.cpp
+++ b/clang/test/CodeGenCXX/lambda-expressions.cpp
@@ -128,3 +128,12 @@ void nestedCapture () {
     };
   };
 }
+
+// Ensure we don't assert here.
+struct CaptureArrayAndThis {
+  CaptureArrayAndThis() {
+    char array[] = "floop";
+    [array, this] {};
+  }
+} capture_array_and_this;
+
-- 
2.7.4