Fix V8 bug 1084

src/scanner-base.cc

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 79 matching lines @@
     }
     x = x * 16 + d;
     Advance();
   }
 
   return x;
 }
 
 
 // Octal escapes of the forms '\0xx' and '\xxx' are not a part of
 // ECMA-262. Other JS VMs support them.

[Lasse Reichstein, 2011/01/31 06:05:19]

Add comment here (or, preferably, at the declaration) saying that it also
accepts the decimal escape "\0".

[Martin Maly, 2011/01/31 22:44:06]

Done.

 uc32 Scanner::ScanOctalEscape(uc32 c, int length) {
-  octal_pos_ = source_pos() - 1;     // Already advanced
   uc32 x = c - '0';
-  for (int i = 0; i < length; i++) {
+  int i = 0;
+  for (; i < length; i++) {
     int d = c0_ - '0';
     if (d < 0 || d > 7) break;
     int nx = x * 8 + d;
     if (nx >= 256) break;
     x = nx;
     Advance();
   }
+  // Allow \0 only. Rest are octal escapes, illegal in strict mode.

[Lasse Reichstein, 2011/01/31 06:05:19]

We "allow" everything (we don't reject anything here), it's just '\0' that isn't
really an octal escape.
Make comment something like "Anything except '\0' is an ocatal escape, which are
illegal in strict mode. Remember position to be able to give a better error
message.".

[Martin Maly, 2011/01/31 22:44:06]

Done.

+  if (c != '\0' || i > 0) {
+    octal_pos_ = source_pos() - i - 1;     // Already advanced
+  }
   return x;
 }
 
 
 // ----------------------------------------------------------------------------
 // JavaScriptScanner
 
 JavaScriptScanner::JavaScriptScanner() : Scanner() {}
 
 
@@ skipping 785 matching lines @@
       if (MatchKeywordStart(input, "with", 1, Token::WITH)) return;
       break;
     case UNMATCHABLE:
       break;
   }
   // On fallthrough, it's a failure.
   state_ = UNMATCHABLE;
 }
 
 } }  // namespace v8::internal