BTW, this blocks tail calls because tail calls will need to know exactly how much space is occupied by the argument area, since the caller and callee will collaborate on managing this space. And that includes any padding above the argument area, and that padding depends on the alignment of the multi-return area.
Bug 1747787 Comment 2 Edit History
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BTW, I think this blocks tail calls because tail calls will need to know exactly how much space is occupied by the argument area, since the caller and callee will collaborate on managing this space. And that includes any padding above the argument area, and that padding depends on the alignment of the multi-return area.