Re: [lmi] Detecting whether move semantics actually take place

[Greg Chicares]

On 10/3/22 15:51, Vadim Zeitlin wrote:
[...]
>  Concepts are very new to me, so I don't have any experience to draw on and
> I don't really know if it's worth starting to use them in this way. I'd at
> least look at the implications for the compilation time because if adding
> these checks makes the code twice slower to compile, it would be a strong
> argument against doing it, IMO.

Looks like the speed penalty is tiny--perhaps a percent or so:

/opt/lmi/src/lmi[0]$git status                    
On branch odd/concepts_smf
nothing to commit, working tree clean
/opt/lmi/src/lmi[0]$make clean                                                  
     
rm --force --recursive /opt/lmi/clang_x86_64-pc-linux-gnu/build/ship
/opt/lmi/src/lmi[0]$time make $coefficiency install check_physical_closure 
>/dev/null
make $coefficiency install check_physical_closure > /dev/null  1633.76s user 
58.65s system 2594% cpu 1:05.24 total

Above is branch odd/concepts_smf; below is master:

/opt/lmi/src/lmi[0]$git switch -
Switched to branch 'master'
Your branch is ahead of 'origin/master' by 1 commit.
  (use "git push" to publish your local commits)
running post-checkout hook...
...post-checkout hook finished.
/opt/lmi/src/lmi[0]$git --no-pager log -1 --oneline 
315b931ed (HEAD -> master) Begin to use 'concepts'
/opt/lmi/src/lmi[0]$git reset --hard origin/master
HEAD is now at f10c11478 Augment documentation
/opt/lmi/src/lmi[0]$make clean                                                  
     
rm --force --recursive /opt/lmi/clang_x86_64-pc-linux-gnu/build/ship
/opt/lmi/src/lmi[0]$time make $coefficiency install check_physical_closure 
>/dev/null
make $coefficiency install check_physical_closure > /dev/null  1626.50s user 
58.02s system 2608% cpu 1:04.57 total