dlang
POC: automatically move scope array literals to the stack
See https://github.com/dlang/dmd/pull/16888#issuecomment-2379226685
Just a proof of concept, I don't think this is worth merging at this stage. Maybe under -preview=dip1000 only.
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I assume you will make
scope foo = [...]@nogc?
If this is actually worth pursuing, yes. It's non-trivial because currently, @nogc is eagerly checked on each expression, while in this case, an array literal expression can only be checked at the end of the function.
That patch could introduce dangling pointers in @safe code. -preview=dip1000 is required to verify the stack-allocated array literal doesn't escape.
-betterC simply disables language features that require druntime, it does not negate @safe or change language semantics in other ways, so checking for global.params.betterC likely isn't the right answer here.