swift

5391887b - [Effects] Ensure that we properly substitute function types in ByClosure checks

[Effects] Ensure that we properly substitute function types in ByClosure checks We weren't substituting generic arguments into function types. In the presence of parameter packs, this could mean that the parameter and argument lists no longer match up, which would cause the effects checker to prematurely bail out after treating this as "invalid" code. The overall effect is that we would not properly check for throwing behavior in this case, allowing invalid code (as in the example) and miscompiling valid code by not treating the call as throwing. Fixes rdar://153926820.