Redefinition and usage of ref type in different scopes leads to invalid c code

[KnorrFG]

It seems that when you define a type with different fields in two different scopes, and instantiate it in both scopes, and accedss a field in the second defintion, that didnt exist in the first definition, the generated c-code will be invalid.

Compiling this:

block:
    type Foo = ref object
    echo Foo().repr
block:
    type Foo = ref object
      field: int
    echo Foo().field

will result in:

[I] felix@rzbl ~/tmp> nim c nimbug.nim
Hint: used config file '/home/felix/git/Nim/config/nim.cfg' [Conf]
Hint: used config file '/home/felix/git/Nim/config/config.nims' [Conf]
....                                                                                                        
CC: stdlib_assertions.nim
CC: stdlib_dollars.nim
CC: stdlib_formatfloat.nim
CC: stdlib_io.nim
CC: stdlib_system.nim
CC: nimbug.nim
/home/felix/.cache/nim/nimbug_d/@mnimbug.nim.c: In function ‘NimMainModule’:
/home/felix/.cache/nim/nimbug_d/@mnimbug.nim.c:191:30: error: ‘tyObject_FoocolonObjectType___fGcm43VB58lQvE79caF19bjQ’ {aka ‘struct tyObject_FoocolonObjectType___fGcm43VB58lQvE79caF19bjQ’} has no member named ‘field’  191 |   T5_[0] = nimIntToStr((*T6_).field);
      |                              ^
Error: execution of an external compiler program 'gcc -c  -w -fmax-errors=3   -I/home/felix/git/Nim/lib -I/home/felix/tmp -o /home/felix/.cache/nim/nimbug_d/@mnimbug.nim.c.o /home/felix/.cache/nim/nimbug_d/@mnimbug.nim.c' failed with exit code: 1

Also:

[I] felix@rzbl ~/tmp> nim -v
Nim Compiler Version 1.5.1 [Linux: amd64]
Compiled at 2021-04-04
Copyright (c) 2006-2021 by Andreas Rumpf

git hash: 97764c8dc91081875f57029ae3f72d3a503f5e45
active boot switches: -d:release

[ringabout]

Duplicate of #15526