From: George M. Garner Jr. (gmgarner_at_[hidden])
Date: 2005-12-11 14:49:39
John,
I think that the problem is at regex_traits_defaults.hpp line 191:
static const character_pointer_range<charT>* ranges_end = ranges +
(sizeof(ranges)/sizeof(ranges[0]));
Your algorithm doesn't allow for compiler data alignment. With 8-byte data
alignment (now the default with VC8) sizeof(ranges) == ((19*4)/8+1)*8 == 80.
The compiler warning is correct get_default_class_id() may return a value
between -1 and 20. Add 1 to this return value and you get a range of 0-21
which exceeds the size of masks in
lookup_classname_imp().
Note that similar code at win32_regex_traits.hpp line 536 is not affected
because the size of masks is 8-byte aligned (for now at least). 64-bit
compilers require 8-byte alignment so I assume that this code will not
compile correctly on those platforms as well.
If you must use this construct ("sizeof(ranges)/sizeof(ranges[0]") then
static assert that this formula yields the same size as your array.
I see that there are a few other non-trivial warnings in my build of the
regex library. My examples were not intended to be exhaustive but to
illustrate the utility of incorporating this into boost's QA.
Regards,
George.