signal_template.hpp uses 'new' to create shared_ptr when it should use make_shared

[BrianWeed]

boost_1_78_0\boost\signals2\detail\signal_template.hpp lines 156, 309, 478, 500, and 513 use 'new' when make_shared would be more efficient. ( There's probably even more places in the code base that could use make_shared, but lines 156, and 513 were the ones flagged by the profiler, and are unnecessary bottlenecks).

Calling new to create a shared pointer forces an additional allocation for the shared count (new sp_counted_impl_p).
Using make_shared, on the other hand, combines the allocations into one, thereby cutting the total number of allocations/deallocations in half.

[fmhess]

Using make_shared sounds fine, would you make a pull request to the develop branch with the changes? If not, let me know and I'll make the changes later.

[BrianWeed]

I’m not really setup to contribute changes right now. It would be ideal if you could do it. Thanks.

…

Sent from my iPad

On Feb 15, 2022, at 5:47 PM, Frank Mori Hess ***@***.***> wrote:  Using make_shared sounds fine, would you make a pull request to the develop branch with the changes? If not, let me know and I'll make the changes later. — Reply to this email directly, view it on GitHub, or unsubscribe. Triage notifications on the go with GitHub Mobile for iOS or Android. You are receiving this because you authored the thread.

[fmhess]

These changes have been merged to master, so should be in boost 1.80