Travis Vitek wrote:
Martin Sebor wrote:
Travis Vitek wrote:
Martin Sebor wrote:
I searched library headers and sources for how we define unions and
with the exception of limits_bits.cpp we always follow this rule.
Unless there is a reason not to make this change to aligned_union,
I think we should change both limits_bits.cpp and aligned_union to
always define the member with the more strict alignment requirement
first, just for peace of mind.
Is there any reason/advantage to having the char buffer first?
If the first member is used to define the alignment, then you have to
know (at compile time) which of the union members has the strictest
alignment requirement so that it can be put first.
Yes. But putting the char buffer first doesn't obviate the
need to do this, does it?
No, I'm just poking another hole in the policy of always putting the
most strictly aligned member first. If I can't reliably determine the
most strictly aligned member, it makes it a tad difficult to declare it
first.
So now the policy becomes 'put the one that you think has the most
stringent alignment requirement on platform X'.
That's essentially been the guideline in existing code.
What do you suggest as an improvement?
Martin
