bug with CTFE std.array.array ?

[Jonathan M Davis]

On Wednesday, July 10, 2013 18:06:00 Timothee Cour wrote:
> import std.array;
> 
> void main(){
> //enum a1=[1].array;//NG: Error: gc_malloc cannot be interpreted at
> compile time
> enum a2=" ".array;//OK
> 
> import std.string;
> //enum a3=" ".splitLines.array;//NG
> enum a4="".splitLines.array;//OK
> enum a5=" ".split.array;//OK
> //enum a6=" a ".split.array;//NG
> import std.algorithm:filter;
> enum a7=" a ".split.filter!(a=>true).array;
> auto a8=" a ".split.array;
> assert(a8==a7);
> enum a9=[1].filter!(a=>true).array;//OK
> }
> 
> 
> I don't understand why the NG above fail (with Error: gc_malloc cannot be
> interpreted at compile time)
> 
> furthermore, it seems we can bypass the CT error with interleaving
> filter!(a=>true) (see above), which is even weirder.

I expect that it's a matter of code path. Some code paths don't hit anything 
which is illegal in CTFE, but apparently at least one of them uses gc_malloc, 
which is apparently illegal in CTFE, so when it gets hit, CTFE fails. 
Presumably, to fix it, either it needs to be changed to not use gc_malloc or 
changed so that it doesn't use gc_malloc with CTFE (by using __ctfe). I'd have 
to actually dig through the code to verify exactly what it's doing though.

- Jonathan M Davis