[Parser][ObjC] Use an artificial EOF token while parsing lexed ObjC methods

hyp · hyp · commit 812012f3c94d · 2017-06-19T17:53:21.000Z
This change avoid a crash that occurred when skipping to EOF while parsing an ObjC interface/implementation. rdar://31963299 Differential Revision: https://reviews.llvm.org/D34185 llvm-svn: 305719
diff --git a/clang/lib/Parse/ParseObjc.cpp b/clang/lib/Parse/ParseObjc.cpp
@@ -3627,6 +3627,14 @@ void Parser::ParseLexedObjCMethodDefs(LexedMethod &LM, bool parseMethod) {
   SourceLocation OrigLoc = Tok.getLocation();
 
   assert(!LM.Toks.empty() && "ParseLexedObjCMethodDef - Empty body!");
+  // Store an artificial EOF token to ensure that we don't run off the end of
+  // the method's body when we come to parse it.
+  Token Eof;
+  Eof.startToken();
+  Eof.setKind(tok::eof);
+  Eof.setEofData(MCDecl);
+  Eof.setLocation(OrigLoc);
+  LM.Toks.push_back(Eof);
   // Append the current token at the end of the new token stream so that it
   // doesn't get lost.
   LM.Toks.push_back(Tok);
@@ -3658,7 +3666,7 @@ void Parser::ParseLexedObjCMethodDefs(LexedMethod &LM, bool parseMethod) {
       Actions.ActOnDefaultCtorInitializers(MCDecl);
     ParseFunctionStatementBody(MCDecl, BodyScope);
   }
-  
+
   if (Tok.getLocation() != OrigLoc) {
     // Due to parsing error, we either went over the cached tokens or
     // there are still cached tokens left. If it's the latter case skip the
@@ -3670,4 +3678,6 @@ void Parser::ParseLexedObjCMethodDefs(LexedMethod &LM, bool parseMethod) {
       while (Tok.getLocation() != OrigLoc && Tok.isNot(tok::eof))
         ConsumeAnyToken();
   }
+  // Clean up the remaining EOF token.
+  ConsumeAnyToken();
 }
diff --git a/clang/test/Parser/objc-at-implementation-eof-crash.m b/clang/test/Parser/objc-at-implementation-eof-crash.m
@@ -0,0 +1,21 @@
+// RUN: %clang_cc1 -verify -Wno-objc-root-class %s
+
+@interface ClassA
+
+- (void)fileExistsAtPath:(int)x;
+
+@end
+
+@interface ClassB
+
+@end
+
+@implementation ClassB // expected-note {{implementation started here}}
+
+- (void) method:(ClassA *)mgr { // expected-note {{to match this '{'}}
+  mgr fileExistsAtPath:0
+} // expected-error {{expected ']'}}
+
+@implementation ClassC // expected-error {{missing '@end'}} // expected-error {{expected '}'}} // expected-warning {{cannot find interface declaration for 'ClassC'}}
+
+@end
diff --git a/clang/test/Parser/objc-at-interface-eof-crash.m b/clang/test/Parser/objc-at-interface-eof-crash.m
@@ -0,0 +1,21 @@
+// RUN: %clang_cc1 -verify -Wno-objc-root-class %s
+
+@interface ClassA
+
+- (void)fileExistsAtPath:(int)x;
+
+@end
+
+@interface ClassB
+
+@end
+
+@implementation ClassB // expected-note {{implementation started here}}
+
+- (void) method:(ClassA *)mgr { // expected-note {{to match this '{'}}
+  mgr fileExistsAtPath:0
+} // expected-error {{expected ']'}}
+
+@interface ClassC // expected-error {{missing '@end'}} // expected-error {{expected '}'}}
+
+@end
