This time for a more limited range of values so that equal values turn
up more often. This is a bit shoddy, but seems like the best way to
improve the existing tests without too much effort.
This was causing the hash function to be different to the equality
function. For some reason this resulted in a lot of windows test
failures, but none on linux or os x. I'm a bit confused and worried
about that.
So currently on one intel tester find_tests is failing the 'pos !=
x.end()' test, but not the 'const_pos != x_const.end()' test for
unordered_set (and possibly others, the test results are truncated). I'm
a bit stumped as to why this should be, as for unordered_set the const
and non-const versions are basically the exact same code. See if
changing the order makes any difference to what fails.
The hash and key equality functions were assigned before allocating new
buckets. If that allocation failed, then the existing elements would be
left in place - so if accessed after the exception they could be in the
wrong buckets or equivalent elements could be incorrectly grouped
together.
AFAICT it's not needed since the construct arguments and the members are
the same reference type. Maybe it was for older compilers? And it appears
to be causing issues with string literals in older versions of Visual
C++.
It seems my defect report was accepted at some point, and they tweaked
the requirements involving bucket counts. This also makes it possible to
have a bucket count of 0, which I think wasn't allowed in the past. I
don't think I'll change this implementation to do so, but I'd like to be
able to run these tests against standard implementations, so I'm
starting to take that into account.
I believe these changes were made after the C++14 standard, but I've
always been tracking the draft standards, so that doesn't really matter.
