Fix V8 bug 1084

src/scanner-base.cc

Index: src/scanner-base.cc
diff --git a/src/scanner-base.cc b/src/scanner-base.cc
index e141d0eb70726bddab28d09c3540767cf0ef754d..91ea9e5133afa54905f2e7e71d45d792bd95fbe5 100644
--- a/src/scanner-base.cc
+++ b/src/scanner-base.cc
@@ -99,9 +99,9 @@ uc32 Scanner::ScanHexEscape(uc32 c, int length) {
 // 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;
@@ -109,6 +109,10 @@ uc32 Scanner::ScanOctalEscape(uc32 c, int length) {
     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;
 }