New @safe rule: defensive closures

[Siarhei Siamashka]

On Friday, 27 May 2022 at 22:16:30 UTC, Steven Schveighoffer 
wrote:
> Consider that there are already so many cases where closures 
> are allocated, with std.algorithm and lambdas, and mostly 
> nobody bats an eye.

Nobody bats an eye when it's DMD doing something as silly as 
allocating closures on heap, because low performance is pretty 
much expected and normal for it. But if this problem also affects 
GDC, then I'm very much concerned about it: 
https://forum.dlang.org/thread/myiqlzkghnnyykbyksga@forum.dlang.org