Open Radar

 
Swift bridges with the C stdlib math functions directly, which is workable. However, the lack of type-safe generic math functions makes doing type-ambiguous math work extremely difficult - particularly when ambiguous types, like CoreGraphics' CGFloat is in play.

Steps to reproduce:
1. Set up an iOS project.
2. In any view/layer/UIKit-related class, set up some frame math
3. Make the unfortunate decision to round/floor/ceil
4. Add Double() or Float() casts to make builds succeed
5. Switch to the opposite bit-width platform/simulator target
6. Add Double() or Float() casts to make builds succeed
7. Switch to the opposite bit-width platform/simulator target
8. Repeat... 

Expected results:
Swift supports function overloading; overloaded math functions should exist that supplant the Darwin.C.math and Darwin.C.tgmath ones, as in C++.

Actual results:
A developer is required to choose between, for example, floor and floorf and aggressively cast/initialize new Double() or Float(), and the "casts" that worked to make one platform compile will not work on another.

Configuration:
Occurs primarily when building an application in Swift that targets both 32-bit and 64-bit platforms simultaneously.

Additional Notes:
Using Darwin.C.tgmath's __tg_floor et. al. produces linker errors, as the Swift compiler refuses to inline the tgmath functions from the Clang stdlib's header.