Bug 15145 – Array initializers for SIMD not working inside functions.

Practically this compiles: import core.simd, std.range, std.array; ubyte[16] a = ubyte(16).iota.array; ubyte16 b = ubyte(16).iota.array; But simply moving the definition inside a function does not work: void main() { import core.simd, std.range, std.array; ubyte16 b = ubyte(16).iota.array; } Error: cannot implicitly convert expression (array(iota(cast(ubyte)16u))) of type ubyte[] to __vector(ubyte[16]) To be fair it works when you declare the vector as static, and that should probably be done for performance, but it should not be an error and the message is too general, as it works for static/global vectors.

It looks like CTFE is evaluating it, and hence can determine the array dimensions so it can be converted. For the runtime evaluation, the array dimension is not available. Not sure what to do about this - D isn't supposed to speculatively attempt to CTFE expressions meant to be evaluated at runtime.

Ah right, now that you say it. I thought it had to do with handling of SSE types in the compiler. I close it as invalid then.