Merge remote-tracking branch 'origin/master' into master-next

Author: swift-ci

include/swift/Parse/Parser.h

@@ -306,30 +306,34 @@ class Parser {
 
   /// An RAII object that notes when we have seen a structure marker.
   class StructureMarkerRAII {
-    Parser &P;
+    Parser *const P;
 
     /// Max nesting level
     // TODO: customizable.
     enum { MaxDepth = 256 };
 
-    void diagnoseOverflow();
+    StructureMarkerRAII(Parser *parser) : P(parser) {}
+
+    /// Have the parser start the new Structure or fail if already too deep.
+    bool pushStructureMarker(Parser &parser, SourceLoc loc,
+                             StructureMarkerKind kind);
 
   public:
-    StructureMarkerRAII(Parser &parser, SourceLoc loc,
-                               StructureMarkerKind kind)
-      : P(parser) {
-      P.StructureMarkers.push_back({loc, kind, None});
-
-      if (P.StructureMarkers.size() >= MaxDepth) {
-        diagnoseOverflow();
-        P.cutOffParsing();
-      }
-    }
+    StructureMarkerRAII(Parser &parser, SourceLoc loc, StructureMarkerKind kind)
+        : StructureMarkerRAII(
+              pushStructureMarker(parser, loc, kind) ? &parser : nullptr) {}
 
     StructureMarkerRAII(Parser &parser, const Token &tok);
 
+    /// Did we fail to push the new structure?
+    bool isFailed() {
+      return P == nullptr;
+    }
+
     ~StructureMarkerRAII() {
-      P.StructureMarkers.pop_back();
+      if (P != nullptr) {
+        P->StructureMarkers.pop_back();
+      }
     }
   };
   friend class StructureMarkerRAII;

lib/Parse/ParseExpr.cpp

@@ -2888,6 +2888,10 @@ ParserStatus Parser::parseExprList(tok leftTok, tok rightTok,
   trailingClosure = nullptr;
 
   StructureMarkerRAII ParsingExprList(*this, Tok);
+  
+  if (ParsingExprList.isFailed()) {
+    return makeParserError();
+  }
 
   leftLoc = consumeToken(leftTok);
   ParserStatus status = parseList(rightTok, leftLoc, rightLoc,

lib/Parse/ParseGeneric.cpp

@@ -55,6 +55,10 @@ Parser::parseGenericParametersBeforeWhere(SourceLoc LAngleLoc,
     // Note that we're parsing a declaration.
     StructureMarkerRAII ParsingDecl(*this, Tok.getLoc(),
                                     StructureMarkerKind::Declaration);
+    
+    if (ParsingDecl.isFailed()) {
+      return makeParserError();
+    }
 
     // Parse attributes.
     DeclAttributes attributes;

lib/Parse/ParsePattern.cpp

@@ -1038,6 +1038,9 @@ ParserResult<Pattern> Parser::parsePatternTuple() {
   SyntaxParsingContext TuplePatternCtxt(SyntaxContext,
                                         SyntaxKind::TuplePattern);
   StructureMarkerRAII ParsingPatternTuple(*this, Tok);
+  if (ParsingPatternTuple.isFailed()) {
+    return makeParserError();
+  }
   SourceLoc LPLoc = consumeToken(tok::l_paren);
   SourceLoc RPLoc;
 

lib/Parse/ParseStmt.cpp

@@ -1250,6 +1250,11 @@ ParserResult<PoundAvailableInfo> Parser::parseStmtConditionPoundAvailable() {
   }
 
   StructureMarkerRAII ParsingAvailabilitySpecList(*this, Tok);
+
+  if (ParsingAvailabilitySpecList.isFailed()) {
+    return makeParserError();
+  }
+    
   SourceLoc LParenLoc = consumeToken(tok::l_paren);
 
   SmallVector<AvailabilitySpec *, 5> Specs;

lib/Parse/ParseType.cpp

@@ -852,6 +852,11 @@ ParserResult<TypeRepr> Parser::parseOldStyleProtocolComposition() {
 ParserResult<TupleTypeRepr> Parser::parseTypeTupleBody() {
   SyntaxParsingContext TypeContext(SyntaxContext, SyntaxKind::TupleType);
   Parser::StructureMarkerRAII ParsingTypeTuple(*this, Tok);
+   
+  if (ParsingTypeTuple.isFailed()) {
+    return makeParserError();
+  }
+
   SourceLoc RPLoc, LPLoc = consumeToken(tok::l_paren);
   SourceLoc EllipsisLoc;
   unsigned EllipsisIdx;

lib/Parse/Parser.cpp

@@ -757,39 +757,42 @@ bool Parser::parseEndIfDirective(SourceLoc &Loc) {
   return false;
 }
 
-Parser::StructureMarkerRAII::StructureMarkerRAII(Parser &parser,
-                                                 const Token &tok)
-  : P(parser)
-{
+static Parser::StructureMarkerKind
+getStructureMarkerKindForToken(const Token &tok) {
   switch (tok.getKind()) {
   case tok::l_brace:
-    P.StructureMarkers.push_back({tok.getLoc(),
-                                  StructureMarkerKind::OpenBrace,
-                                  None});
-    break;
-
+    return Parser::StructureMarkerKind::OpenBrace;
   case tok::l_paren:
-    P.StructureMarkers.push_back({tok.getLoc(),
-                                  StructureMarkerKind::OpenParen,
-                                  None});
-    break;
-
+    return Parser::StructureMarkerKind::OpenParen;
   case tok::l_square:
-    P.StructureMarkers.push_back({tok.getLoc(),
-                                  StructureMarkerKind::OpenSquare,
-                                  None});
-    break;
-
+    return Parser::StructureMarkerKind::OpenSquare;
   default:
     llvm_unreachable("Not a matched token");
   }
 }
 
-void Parser::StructureMarkerRAII::diagnoseOverflow() {
-  auto Loc = P.StructureMarkers.back().Loc;
-  P.diagnose(Loc, diag::structure_overflow, MaxDepth);
-}
+Parser::StructureMarkerRAII::StructureMarkerRAII(Parser &parser,
+                                                 const Token &tok)
+    : StructureMarkerRAII(parser, tok.getLoc(),
+                          getStructureMarkerKindForToken(tok)) {}
 
+bool Parser::StructureMarkerRAII::pushStructureMarker(
+                                      Parser &parser, SourceLoc loc,    
+                                      StructureMarkerKind kind) {
+  
+  if (parser.StructureMarkers.size() < MaxDepth) {
+    parser.StructureMarkers.push_back({loc, kind, None});
+    return true;
+  } else {
+    parser.diagnose(loc, diag::structure_overflow, MaxDepth);
+    // We need to cut off parsing or we will stack-overflow.
+    // But `cutOffParsing` changes the current token to eof, and we may be in
+    // a place where `consumeToken()` will be expecting e.g. '[',
+    // since we need that to get to the callsite, so this can cause an assert.
+    parser.cutOffParsing();
+    return false;
+  }
+}
 //===----------------------------------------------------------------------===//
 // Primitive Parsing
 //===----------------------------------------------------------------------===//

test/Parse/structure_no_overflow.swift

@@ -0,0 +1,37 @@
+// RUN: %target-swift-frontend -parse %s 2>&1 | %FileCheck -allow-empty %s
+
+// Test that we can have the allowed # of parens.
+// CHECK-NOT: error
+let a = (((((((((((((((((((((((((((((((( ((((((((((((((((((((((((((((((((
+        (((((((((((((((((((((((((((((((( ((((((((((((((((((((((((((((((((
+        (((((((((((((((((((((((((((((((( ((((((((((((((((((((((((((((((((
+        (((((((((((((((((((((((((((((((( ((((((((((((((((((((((((((((((
+        1
+          )))))))))))))))))))))))))))))) ))))))))))))))))))))))))))))))))
+        )))))))))))))))))))))))))))))))) ))))))))))))))))))))))))))))))))
+        )))))))))))))))))))))))))))))))) ))))))))))))))))))))))))))))))))
+        )))))))))))))))))))))))))))))))) ))))))))))))))))))))))))))))))))
+
+// Test that we can have the allowed # of curly braces.
+/// CHECK-NOT: error
+let b = {{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{ {{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{
+        {{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{ {{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{
+        {{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{ {{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{
+        {{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{ {{{{{{{{{{{{{{{{{{{{{{{{{{{{{{
+        1
+          }}}}}}}}}}}}}}}}}}}}}}}}}}}}}} }}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}
+        }}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}} }}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}
+        }}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}} }}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}
+        }}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}} }}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}
+
+// Test that we can have the allowed # of mixed brackets.
+// CHECK-NOT: error
+let c = ({({({({ ({({({([ ({({({({ ({({({([  ({({({({ ({({({([ ({({({({ ({({({({
+        ({({({({ ({({({([ ({({({({ ({({({([  ({({({({ ({({({([ ({({({({ ({({({({
+        ({({({({ ({({({([ ({({({({ ({({({([  ({({({({ ({({({([ ({({({({ ({({({({
+        ({({({({ ({({({([ ({({({({ ({({({([  ({({({({ ({({({([ ({({({({ ({({({
+        1
+          })})}) })})})}) ])})})}) })})})})  ])})})}) })})})}) ])})})}) })})})}) 
+        })})})}) })})})}) ])})})}) })})})})  ])})})}) })})})}) ])})})}) })})})}) 
+        })})})}) })})})}) ])})})}) })})})})  ])})})}) })})})}) ])})})}) })})})}) 
+        })})})}) })})})}) ])})})}) })})})})  ])})})}) })})})}) ])})})}) })})})})