Error: attempt to access a nil address kind: rkInt (caused by result[^1])

[treeform]

New bug in devel: result[^1] breaks inside macros but result[len-1] work.

Example

import macros

proc bar(): string =
  result = "hi"
  echo result[^1]

macro foo() =
  echo bar()

foo()

Current Output

stack trace: (most recent call last)
C:\p\jsony\tests\foo.nim(8, 11) foo
C:\p\jsony\tests\foo.nim(5, 14) bar
C:\p\jsony\tests\foo.nim(10, 4) template/generic instantiation of `foo` from here
C:\p\jsony\tests\foo.nim(5, 14) Error: attempt to access a nil address kind: rkInt

Expected Output

during compile:

i
hi

Possible Solution

Worked on 1.4.0, breaks now.

This result[result.len-1] works though:

import macros

proc bar(): string =
  result = "hi"
  echo result[result.len-1]

macro foo() =
  echo bar()

foo()

nim c -v
Nim Compiler Version 1.5.1 [Windows: amd64]
Compiled at 2020-12-02
Copyright (c) 2006-2020 by Andreas Rumpf

active boot switches: -d:release```

[metagn]

#15461 causes this, might be solved by #15987

[treeform]

That's cool. I hope the fix will come out soon.

[timotheecour]

I confirm that #15987 does fix this issue (and many others)

[treeform]

Great, thank you!