Can't check if stderr is static

[PMunch]

While working on Futhark I wanted to decide whether or not to put something into a const or a let. Basically it tries to read out macros which can resolve to simple numbers and I want those to be consts, but it can also be other stuff which can't go into a const. I came if with a solution of using when x is static: const y = x else: let y = x which works fine for most identifiers. But certain built-ins like stdout and stderr makes the compiler crash.

Example

when stderr is static:
  echo "whoops"
else:
  echo "works"

Current Output

fatal.nim(53)            sysFatal
Error: unhandled exception: index -1 not in 0 .. 0 [IndexDefect]

Expected Output

works

Possible Solution

Not really sure what a possible solution would be, but building a debug compiler gives a lot more output to work with.

[Cloudperry]

Your code might be triggering the same underlying compiler bug that I hit with nim-regex. The last 6 lines of the debug compiler stack trace are the same as with the code here: nitely/nim-regex#107. Idk if this is helpful at all, because it seems your code is a simpler way to trigger the same bug.

[ringabout]

built-ins like stdout and stderr are importc symbols

see #19709

It is a regression since 1.2.0 caused by #12877