On 16 August 2011 12:54, Jeffrey Walton <noloader@xxxxxxxxx> wrote: > On Mon, Aug 15, 2011 at 7:43 PM, Jonathan Wakely <jwakely.gcc@xxxxxxxxx> wrote: >> On 16 August 2011 00:30, Jeffrey Walton wrote: >>> Hi All, >>> >>> I'm testing a custom allocator. The allocator works well with vector, >>> but fails to link with basic_string (see below). >>> >>> I looked through Stroustrup and could not find info on _Alloc_hider. >> >> It starts with an underscore followed by an upper case letter, so it's >> in the implementation namespace i.e. it's an implementation detail, so >> you're not going to find it in a book. >> >> [SNIP] >>> >>> How does one one provided an allocator for use by a basic_string? >> >> By writing a type that meets the C++03 Allocator requirements, which >> yours doesn't. >> >> If you look at the source you'll see that _Alloc_hider is a type >> derived from the string's allocator_type, which is done to benefit >> from the Empty Base Optimization. Since it is derived from the >> string's allocator type, it is convertible to the allocator type,... > Forgot to ask.... What are the C++03 retirements being violated? Or Your type isn't CopyConstructible because the copy constructor is explicit. basic_string::get_allocator() returns by value, which requires CopyConstructible. > better, does GCC publish a specification? (I don't have a bootleg copy > of the ISO/IEC copyrighted material). Why would it have to be a bootleg copy? You can buy legal copies electronically or as a book.
