toSeq result can't be assigned to a const inside a generic proc

[dawkot]

Example

import sequtils

proc myProc[T](x: T) =
  const myConst = toSeq(1..3)

myProc 123

Current Output

/usercode/in.nim(6, 8) template/generic instantiation of `myProc` from here
/playground/nim/lib/pure/collections/sequtils.nim(712, 11) Error: cannot evaluate at compile time: i`gensym3690237

Workaround

import sugar

proc myProc[T](x: T) =
  const myConst = collect(newSeq, for i in 1..3: i)

myProc 123

Additional Information

• Nim 1.2.0

[metagn]

Compiler SIGSEGVs if you do:

import sequtils

proc myProc[T](x: T) =
  const myConst = static(toSeq(1..3))

myProc 123

[timotheecour]

• @dawkot this has nothing to do with generics, when you state can't be assigned to a const inside a generic proc you really have to check whether it would instead work inside a non-generic.
  It turns out it also doesn't work:

when true:
  import sequtils
  proc myProc() =
    const myConst = toSeq(1..3)
  myProc()

=> same error

and in fact this is a duplicate of #13795

• @hlaaftana the SIGSEGV mentioned here: toSeq result can't be assigned to a const inside a generic proc  #14192 (comment) is a different bug, I've reduced it here: compiler crash: findUnresolvedStatic  #14802