[PATCH] Limit includes in hashtable_policy.h

[Jonathan Wakely]

On 27/02/20 19:30 +0100, François Dumont wrote:
>When I use std::is_permutation in hashtable_policy.h I included 
>stl_algo.h which is a large header. No other header in include/bits 
>does this, I would prefer not being the first to do such a thing.
>
>As it is a recent change I prefer to submit this patch now.
>
>Git commit message:
>
>    libstdc++ Hashtable: Move std::is_permutation to limit includes
>
>    * include/bits/stl_algo.h (__find_if, __count_if, 
>std::is_permutation): Move...
>    * include/bits/stl_algobase.h: ...here.
>    * include/bits/hashtable_policy.h: Remove <bits/stl_algo.h> include.
>
>testsuite/23_containers/unordered* tested under Linux x86_64, I'll run 
>full before any commit.
>
>Ok to commit now ?
>
>Ok to commit once back in stage 1 ?

I was already thinking of doing something like this in stage 1. But
you're right that this is a recent regression on master. Before
<bits/stl_algo.h> got added the preprocessed size of <unordered_map>
had got much smaller due to <array> no longer including <stdexcept>.
But including <bits/stl_algo.h> made it almost the same size as in
gcc-9 again.

With your patch we remove 7kloc from <unordered_map> again.

OK for master now, thanks.