std.math: Move most of the rounding functions into submodule.

[berni44]

I left out floor and ceil because moving floorImpl to the submodule fails with a strange error message. I guess, there is some compiler magic involved here, making union work in CTFE.

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[berni44]

Here compilable/test5227.d fails. It's two function that cannot be evaluated at runtime: round and trunc. Looks, like the calls to core.stdc.math.roundl and core.stdc.math.truncl in CTFE are restricted to std.math, but cannot be called from std.math.rounding.

[berni44]

It's not the calls I mentioned above. So I suspect dmd searching round and trunc in std.math and not in std.math.rounding; that is, the public imports are ignored... I need help here from someone who knows the inner workings of dmd.

[thewilsonator]

https://github.com/dlang/dmd/blob/master/src/dmd/builtin.d#L91 is the function in question.

[RazvanN7]

Have you tried making a public alias to the symbols that were moved to the submodules? That should work.

Otherwise, we can make the compiler acknowledge the new submodules, although I would rather not go down that route.

[berni44]

Have you tried making a public alias to the symbols that were moved to the submodules? That should work.

Wouldn't that clash with the public imports? I'll check it out.

[berni44]

Didn't clash, so I probably do not understand something with visibility and scope... But that's my fault. I'll try to pick that up.

Anyway, the error has not vanished, but this time brought up a new detail:

D:\a\1\dmd\test\..\..\phobos\std\math\package.d(4851): Error: `asm` statements cannot be interpreted at compile time
D:\a\1\dmd\test\..\..\phobos\std\math\rounding.d(437):        called from here: `getControlState()`
compilable\test5227.d(70):        called from here: `round(5.5L)`
compilable\test5227.d(70):        while evaluating `pragma(msg, roundr)`

Line 4851 of package.d is inside getControlState() of FloatingPointControl.

[ibuclaw]

Squash and add missing versions.