1 files changed, 39 insertions, 29 deletions

diff --git a/include/clang/Parse/Parser.h b/include/clang/Parse/Parser.h
index f5c70e71b8..db0217324b 100644
--- a/include/clang/Parse/Parser.h
+++ b/include/clang/Parse/Parser.h
@@ -363,10 +363,28 @@ class Parser : public CodeCompletionHandler {
   /// just a regular sub-expression.
   SourceLocation ExprStatementTokLoc;
 
-  /// Tests whether an expression value is discarded based on token lookahead.
-  /// It will return true if the lexer is currently processing the })
-  /// terminating a GNU statement expression and false otherwise.
-  bool isExprValueDiscarded();
+  /// Flags describing a context in which we're parsing a statement.
+  enum class ParsedStmtContext {
+    /// This context permits declarations in language modes where declarations
+    /// are not statements.
+    AllowDeclarationsInC = 0x1,
+    /// This context permits standalone OpenMP directives.
+    AllowStandaloneOpenMPDirectives = 0x2,
+    /// This context is at the top level of a GNU statement expression.
+    InStmtExpr = 0x4,
+
+    /// The context of a regular substatement.
+    SubStmt = 0,
+    /// The context of a compound-statement.
+    Compound = AllowDeclarationsInC | AllowStandaloneOpenMPDirectives,
+
+    LLVM_MARK_AS_BITMASK_ENUM(InStmtExpr)
+  };
+
+  /// Act on an expression statement that might be the last statement in a
+  /// GNU statement expression. Checks whether we are actually at the end of
+  /// a statement expression and builds a suitable expression statement.
+  StmtResult handleExprStmt(ExprResult E, ParsedStmtContext StmtCtx);
 
 public:
   Parser(Preprocessor &PP, Sema &Actions, bool SkipFunctionBodies);
@@ -1873,29 +1891,24 @@ private:
   /// A SmallVector of types.
   typedef SmallVector<ParsedType, 12> TypeVector;
 
-  StmtResult ParseStatement(SourceLocation *TrailingElseLoc = nullptr,
-                            bool AllowOpenMPStandalone = false);
-  enum AllowedConstructsKind {
-    /// Allow any declarations, statements, OpenMP directives.
-    ACK_Any,
-    /// Allow only statements and non-standalone OpenMP directives.
-    ACK_StatementsOpenMPNonStandalone,
-    /// Allow statements and all executable OpenMP directives
-    ACK_StatementsOpenMPAnyExecutable
-  };
   StmtResult
-  ParseStatementOrDeclaration(StmtVector &Stmts, AllowedConstructsKind Allowed,
-                              SourceLocation *TrailingElseLoc = nullptr);
+  ParseStatement(SourceLocation *TrailingElseLoc = nullptr,
+                 ParsedStmtContext StmtCtx = ParsedStmtContext::SubStmt);
+  StmtResult ParseStatementOrDeclaration(
+      StmtVector &Stmts, ParsedStmtContext StmtCtx,
+      SourceLocation *TrailingElseLoc = nullptr);
   StmtResult ParseStatementOrDeclarationAfterAttributes(
                                          StmtVector &Stmts,
-                                         AllowedConstructsKind Allowed,
+                                         ParsedStmtContext StmtCtx,
                                          SourceLocation *TrailingElseLoc,
                                          ParsedAttributesWithRange &Attrs);
-  StmtResult ParseExprStatement();
-  StmtResult ParseLabeledStatement(ParsedAttributesWithRange &attrs);
-  StmtResult ParseCaseStatement(bool MissingCase = false,
+  StmtResult ParseExprStatement(ParsedStmtContext StmtCtx);
+  StmtResult ParseLabeledStatement(ParsedAttributesWithRange &attrs,
+                                   ParsedStmtContext StmtCtx);
+  StmtResult ParseCaseStatement(ParsedStmtContext StmtCtx,
+                                bool MissingCase = false,
                                 ExprResult Expr = ExprResult());
-  StmtResult ParseDefaultStatement();
+  StmtResult ParseDefaultStatement(ParsedStmtContext StmtCtx);
   StmtResult ParseCompoundStatement(bool isStmtExpr = false);
   StmtResult ParseCompoundStatement(bool isStmtExpr,
                                     unsigned ScopeFlags);
@@ -1918,7 +1931,7 @@ private:
   StmtResult ParseAsmStatement(bool &msAsm);
   StmtResult ParseMicrosoftAsmStatement(SourceLocation AsmLoc);
   StmtResult ParsePragmaLoopHint(StmtVector &Stmts,
-                                 AllowedConstructsKind Allowed,
+                                 ParsedStmtContext StmtCtx,
                                  SourceLocation *TrailingElseLoc,
                                  ParsedAttributesWithRange &Attrs);
 
@@ -1984,7 +1997,8 @@ private:
   //===--------------------------------------------------------------------===//
   // Objective-C Statements
 
-  StmtResult ParseObjCAtStatement(SourceLocation atLoc);
+  StmtResult ParseObjCAtStatement(SourceLocation atLoc,
+                                  ParsedStmtContext StmtCtx);
   StmtResult ParseObjCTryStmt(SourceLocation atLoc);
   StmtResult ParseObjCThrowStmt(SourceLocation atLoc);
   StmtResult ParseObjCSynchronizedStmt(SourceLocation atLoc);
@@ -2824,13 +2838,9 @@ private:
       bool AllowScopeSpecifier);
   /// Parses declarative or executable directive.
   ///
-  /// \param Allowed ACK_Any, if any directives are allowed,
-  /// ACK_StatementsOpenMPAnyExecutable - if any executable directives are
-  /// allowed, ACK_StatementsOpenMPNonStandalone - if only non-standalone
-  /// executable directives are allowed.
-  ///
+  /// \param StmtCtx The context in which we're parsing the directive.
   StmtResult
-  ParseOpenMPDeclarativeOrExecutableDirective(AllowedConstructsKind Allowed);
+  ParseOpenMPDeclarativeOrExecutableDirective(ParsedStmtContext StmtCtx);
   /// Parses clause of kind \a CKind for directive of a kind \a Kind.
   ///
   /// \param DKind Kind of current directive.