Issue #12983: Bytes literals with invalid \x escape now raise a SyntaxError

and a full traceback including line number.

diff --cc Misc/NEWS
index 2cfd48460a7c3e354960f95ce4c2a765443de6d6,9c3e3bee3b613b85f69077f1e425884fcb9a1f71..c96627cef89664fbf793a1d77e9b7207a326cde0
--- 1/Misc/NEWS
--- 2/Misc/NEWS
+++ b/Misc/NEWS
@@@ -10,9 -12,9 +10,12 @@@ What's New in Python 3.4.0 Alpha 1
  Core and Builtins
  -----------------
  
+ - Issue #12983: Bytes literals with invalid \x escape now raise a SyntaxError
+   and a full traceback including line number.
+ 
 +- Issue #16967: In function definition, evaluate positional defaults before
 +  keyword-only defaults.
 +
  - Issue #17173: Remove uses of locale-dependent C functions (isalpha() etc.)
    in the interpreter.
  

diff --cc Objects/bytesobject.c
Simple merge

diff --cc Python/ast.c
Simple merge