Boost C++ Libraries: Ticket #3076: [multi_index] assertion failure sorting an empty collection in VC10 Beta 1

status changed; resolution set

Joaquín M López Muñoz — Mon, 25 May 2009 12:20:15 GMT

status new → closed
resolution → fixed

(In [53246]) fixed #3076

Joaquín M López Muñoz — Mon, 25 May 2009 13:00:39 GMT

Hi Richard,

Thanks for reporting this bug. I've just commited a fix:

https://svn.boost.org/trac/boost/changeset/53246

I'd appreciate if you can have keep an eye on this to make sure the problems in bimap eventually disappear.

There's one thing in your description of the problem that puzzles me a bit: you say that std::copy asserts because the third parameter is NULL, yet it seems to me that it's entirely ok to invoke

std::copy(first,last,NULL);

as long as first==last and consequently NULL is not dereferenced. Can you provide me with more info on the kind of assertion failure you're seeing? Can't it rather be the expression &*buf that is failing?

Mon, 25 May 2009 18:26:42 GMT

In VC9, the copy code does the check

_DEBUG_RANGE(_First, _Last); if (_First != _Last)

_DEBUG_POINTER(_Dest);

Wheras VC10 just does

_DEBUG_RANGE(_First, _Last); _DEBUG_POINTER(_Dest);

(Where _DEBUG_POINTER gives an error if _Dest is NULL). So VC9 only complains if Dest is null and theres something to do, but VC10 gives you an error any time it's null.

anonymous — Tue, 26 May 2009 19:13:33 GMT

I see. I'm not entirely sure the VC10 checking is conformant, so I've posted a query to comp.std.c++:

http://tinyurl.com/ouut5e

Let's see what the gurus say.