crashing code

[faassen]

I have a piece of code that crashes as soon as a function gets called. It is dependent on the size of the data and also on how the data is passed into the code.

const WIDTH = 640
const HEIGHT = 327

type
  TField = tuple [
    a: float,
    b: float,
    c: float,
    d: float,
    e: float]
  TRow = array[0..WIDTH - 1, TField]
  TGrid = array[0..HEIGHT -1, TRow]
  TWorld = tuple [grid: TGrid]

proc display(world: TWorld) =
  for r, row in world.grid:
    for c, field in row:
      echo("init " & $(r) & " " & $(c))

var w: TWorld

w.display()

If you modify WIDTH to be one less, the code works. The crash seems to be as soon as the display proc is reached; the display proc isn't even executed. If you add another tuple field to TField the code fails even with HEIGHT 327.

If you modify display to get TGrid as a parameter directly and call display on it, it seems to work for arbitrary HEIGHTs.

[gradha]

It seems the problem is the TWorld tuple being passed as parameter. If the var is changed to a TGrid and that is passed to display the program doesn't crash.

[Araq]

That's a simple stack overflow. The code generator could be improved to avoid it, but for now I'm closing this bug.