Allow TransformTypos to ignore corrections to a specified VarDecl.

This is needed to prevent a TypoExpr from being corrected to a variable
when the TypoExpr is a subexpression of that variable's initializer.

Also exclude more keywords from the correction candidate pool when the
subsequent token is .* or ->* since keywords like "new" or "return"
aren't valid on the left side of those operators.

Fixes PR23140.

llvm-svn: 236519

3 files changed, 21 insertions, 10 deletions

diff --git a/clang/lib/Parse/ParseExpr.cpp b/clang/lib/Parse/ParseExpr.cpp
index 527351012d9..95a28a8d5a1 100644
--- a/clang/lib/Parse/ParseExpr.cpp
+++ b/clang/lib/Parse/ParseExpr.cpp
@@ -931,7 +931,12 @@ ExprResult Parser::ParseCastExpression(bool isUnaryExpression,
     auto Validator = llvm::make_unique<CastExpressionIdValidator>(
         Tok, isTypeCast != NotTypeCast, isTypeCast != IsTypeCast);
     Validator->IsAddressOfOperand = isAddressOfOperand;
-    Validator->WantRemainingKeywords = Tok.isNot(tok::r_paren);
+    if (Tok.is(tok::periodstar) || Tok.is(tok::arrowstar)) {
+      Validator->WantExpressionKeywords = false;
+      Validator->WantRemainingKeywords = false;
+    } else {
+      Validator->WantRemainingKeywords = Tok.isNot(tok::r_paren);
+    }
     Name.setIdentifier(&II, ILoc);
     Res = Actions.ActOnIdExpression(
         getCurScope(), ScopeSpec, TemplateKWLoc, Name, Tok.is(tok::l_paren),
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 00922f73a8e..7f4b3952807 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -8710,7 +8710,7 @@ void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init,
   // If there is no declaration, there was an error parsing it.  Just ignore
   // the initializer.
   if (!RealDecl || RealDecl->isInvalidDecl()) {
-    CorrectDelayedTyposInExpr(Init);
+    CorrectDelayedTyposInExpr(Init, dyn_cast_or_null<VarDecl>(RealDecl));
     return;
   }
 
@@ -8744,11 +8744,12 @@ void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init,
     // Attempt typo correction early so that the type of the init expression can
     // be deduced based on the chosen correction:if the original init contains a
     // TypoExpr.
-    ExprResult Res = CorrectDelayedTyposInExpr(Init);
+    ExprResult Res = CorrectDelayedTyposInExpr(Init, VDecl);
     if (!Res.isUsable()) {
       RealDecl->setInvalidDecl();
       return;
     }
+
     if (Res.get() != Init) {
       Init = Res.get();
       if (CXXDirectInit)
@@ -8967,8 +8968,8 @@ void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init,
 
     // Try to correct any TypoExprs in the initialization arguments.
     for (size_t Idx = 0; Idx < Args.size(); ++Idx) {
-      ExprResult Res =
-          CorrectDelayedTyposInExpr(Args[Idx], [this, Entity, Kind](Expr *E) {
+      ExprResult Res = CorrectDelayedTyposInExpr(
+          Args[Idx], VDecl, [this, Entity, Kind](Expr *E) {
             InitializationSequence Init(*this, Entity, Kind, MultiExprArg(E));
             return Init.Failed() ? ExprError() : E;
           });
diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp
index bb67939ad89..b853eaefbe4 100644
--- a/clang/lib/Sema/SemaExprCXX.cpp
+++ b/clang/lib/Sema/SemaExprCXX.cpp
@@ -6138,6 +6138,8 @@ public:
 class TransformTypos : public TreeTransform<TransformTypos> {
   typedef TreeTransform<TransformTypos> BaseTransform;
 
+  VarDecl *InitDecl; // A decl to avoid as a correction because it is in the
+                     // process of being initialized.
   llvm::function_ref<ExprResult(Expr *)> ExprFilter;
   llvm::SmallSetVector<TypoExpr *, 2> TypoExprs, AmbiguousTypoExprs;
   llvm::SmallDenseMap<TypoExpr *, ExprResult, 2> TransformCache;
@@ -6216,8 +6218,8 @@ class TransformTypos : public TreeTransform<TransformTypos> {
   }
 
 public:
-  TransformTypos(Sema &SemaRef, llvm::function_ref<ExprResult(Expr *)> Filter)
-      : BaseTransform(SemaRef), ExprFilter(Filter) {}
+  TransformTypos(Sema &SemaRef, VarDecl *InitDecl, llvm::function_ref<ExprResult(Expr *)> Filter)
+      : BaseTransform(SemaRef), InitDecl(InitDecl), ExprFilter(Filter) {}
 
   ExprResult RebuildCallExpr(Expr *Callee, SourceLocation LParenLoc,
                                    MultiExprArg Args,
@@ -6296,6 +6298,8 @@ public:
     // For the first TypoExpr and an uncached TypoExpr, find the next likely
     // typo correction and return it.
     while (TypoCorrection TC = State.Consumer->getNextCorrection()) {
+      if (InitDecl && TC.getCorrectionDecl() == InitDecl)
+        continue;
       ExprResult NE = State.RecoveryHandler ?
           State.RecoveryHandler(SemaRef, E, TC) :
           attemptRecovery(SemaRef, *State.Consumer, TC);
@@ -6320,8 +6324,9 @@ public:
 };
 }
 
-ExprResult Sema::CorrectDelayedTyposInExpr(
-    Expr *E, llvm::function_ref<ExprResult(Expr *)> Filter) {
+ExprResult
+Sema::CorrectDelayedTyposInExpr(Expr *E, VarDecl *InitDecl,
+                                llvm::function_ref<ExprResult(Expr *)> Filter) {
   // If the current evaluation context indicates there are uncorrected typos
   // and the current expression isn't guaranteed to not have typos, try to
   // resolve any TypoExpr nodes that might be in the expression.
@@ -6332,7 +6337,7 @@ ExprResult Sema::CorrectDelayedTyposInExpr(
     assert(TyposInContext < ~0U && "Recursive call of CorrectDelayedTyposInExpr");
     ExprEvalContexts.back().NumTypos = ~0U;
     auto TyposResolved = DelayedTypos.size();
-    auto Result = TransformTypos(*this, Filter).Transform(E);
+    auto Result = TransformTypos(*this, InitDecl, Filter).Transform(E);
     ExprEvalContexts.back().NumTypos = TyposInContext;
     TyposResolved -= DelayedTypos.size();
     if (Result.isInvalid() || Result.get() != E) {