Fix a crash-on-valid where a block capture copy expression was

picking up cleanups from earlier in the statement.  Also fix a
crash-on-invalid where a reference to an invalid decl from an
enclosing scope was causing an expression to fail to build, but
only *after* a cleanup was registered from that statement,
causing an assertion downstream.

The crash-on-valid is rdar://13459289.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177692 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 14 insertions, 3 deletions

diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 8213739b4e..5597bf6009 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -7916,6 +7916,7 @@ void Sema::CheckCompleteVariableDeclaration(VarDecl *var) {
     // Regardless, we don't want to ignore array nesting when
     // constructing this copy.
     if (type->isStructureOrClassType()) {
+      EnterExpressionEvaluationContext scope(*this, PotentiallyEvaluated);
       SourceLocation poi = var->getLocation();
       Expr *varRef =new (Context) DeclRefExpr(var, false, type, VK_LValue, poi);
       ExprResult result
diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index dd8dad3df8..52ed28afb9 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -10288,6 +10288,9 @@ VarDecl *Sema::BuildExceptionDeclaration(Scope *S,
 
   if (!Invalid && !ExDeclType->isDependentType()) {
     if (const RecordType *recordType = ExDeclType->getAs<RecordType>()) {
+      // Insulate this from anything else we might currently be parsing.
+      EnterExpressionEvaluationContext scope(*this, PotentiallyEvaluated);
+
       // C++ [except.handle]p16:
       //   The object declared in an exception-declaration or, if the 
       //   exception-declaration does not specify a name, a temporary (12.2) is 
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index e4323c35a6..26a697cfe3 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -10698,7 +10698,7 @@ static ExprResult captureInLambda(Sema &S, LambdaScopeInfo *LSI,
   // Introduce a new evaluation context for the initialization, so
   // that temporaries introduced as part of the capture are retained
   // to be re-"exported" from the lambda expression itself.
-  S.PushExpressionEvaluationContext(Sema::PotentiallyEvaluated);
+  EnterExpressionEvaluationContext scope(S, Sema::PotentiallyEvaluated);
 
   // C++ [expr.prim.labda]p12:
   //   An entity captured by a lambda-expression is odr-used (3.2) in
@@ -10749,7 +10749,6 @@ static ExprResult captureInLambda(Sema &S, LambdaScopeInfo *LSI,
     if (Subscript.isInvalid()) {
       S.CleanupVarDeclMarking();
       S.DiscardCleanupsInEvaluationContext();
-      S.PopExpressionEvaluationContext();
       return ExprError();
     }
 
@@ -10785,7 +10784,6 @@ static ExprResult captureInLambda(Sema &S, LambdaScopeInfo *LSI,
   // Exit the expression evaluation context used for the capture.
   S.CleanupVarDeclMarking();
   S.DiscardCleanupsInEvaluationContext();
-  S.PopExpressionEvaluationContext();
   return Result;
 }
 
@@ -10972,6 +10970,10 @@ bool Sema::tryCaptureVariable(VarDecl *Var, SourceLocation Loc,
             if (isa<ParmVarDecl>(Var))
               FinalizeVarWithDestructor(Var, Record);
 
+            // Enter a new evaluation context to insulate the copy
+            // full-expression.
+            EnterExpressionEvaluationContext scope(*this, PotentiallyEvaluated);
+
             // According to the blocks spec, the capture of a variable from
             // the stack requires a const copy constructor.  This is not true
             // of the copy/move done to move a __block variable to the heap.
diff --git a/lib/Sema/SemaStmt.cpp b/lib/Sema/SemaStmt.cpp
index 0c51e44371..a2dc616deb 100644
--- a/lib/Sema/SemaStmt.cpp
+++ b/lib/Sema/SemaStmt.cpp
@@ -54,6 +54,11 @@ StmtResult Sema::ActOnExprStmt(ExprResult FE) {
 }
 
 
+StmtResult Sema::ActOnExprStmtError() {
+  DiscardCleanupsInEvaluationContext();
+  return StmtError();
+}
+
 StmtResult Sema::ActOnNullStmt(SourceLocation SemiLoc,
                                bool HasLeadingEmptyMacro) {
   return Owned(new (Context) NullStmt(SemiLoc, HasLeadingEmptyMacro));