swift234

Initialize a variable to make the analyzer happy.

The analyzer can't reason about the following complicated
control-dependency:

    if (!isxdigit(BytesPtr[0]) || !isxdigit(BytesPtr[1]) ||
        !isxdigit(BytesPtr[2]) || !isxdigit(BytesPtr[3])
        continue;  // Ignore invalid escapes.
      
    StringRef(BytesPtr, 4).getAsInteger(16, CharValue);
    BytesPtr += 4;

In this case, we cap the number of bytes read at 4, and we have
verified that the bytes will always form an integer.  The analyzer
thinks there could be a false positive uninitialized value warning
here since 'getAsInteger()' does its own checking to see if the
parsed bytes actually compose an integer value.

Swift SVN r5566