Building koch from nim devel fails when config.nims importing `os` present

[kaushalmodi]

I have been able to reproduce this issue on the latest Nim devel as of now ( 0409f23 ).

Steps to reproduce the issue

1. Build koch using the csources-built nim binary as you would normally do when building Nim from devel.
2. Create a ~/.config/nim/config.nims with just import os line.
3. In your Nim build dir, where you build koch, do ./koch boot -d:release.

You will get something like:

km²~/downloads/:git/Nim> ./koch boot -d:release                 12/17 2:46pm
iteration: 1
compiler/nim0 c -d:release --nimcache:nimcache/r_linux_amd64 compiler/nim.nim
Hint: used config file '/home/kmodi/downloads/git/Nim/config/nim.cfg' [Conf]
Hint: used config file '/home/kmodi/downloads/git/Nim/compiler/nim.cfg' [Conf]
Hint: used config file '/home/kmodi/.config/nim/config.nims' [Conf]
../lib/system.nim(376, 50) Warning: unknown magic 'Destroy' might crash the compiler [UnknownMagic]
../lib/pure/os.nim(705, 14) Error: undeclared identifier: 'Stat'
FAILURE

---

An ugly workaround I use to allow Nim devel to build successfully on Travis is to temporarily remove the config.nims from Nim's search path: kaushalmodi/hello_musl@ed97b4b

/cc @nc-x, @Araq

[kaushalmodi]

(moved to #10031)

[timotheecour]

@kaushalmodi remember to use permalinks instead of links to master, which are mutable, eg: https://github.com/kaushalmodi/nim_config/blob/e38fb2d1c5d70b1ee2fe47683b706d1059f352a2/config.nims#L1

[timotheecour]

Note that even though the --skipUserCfg option is available for the csources-build nim binary, it doesn't work..
See below that it still is fetching /home/kmodi/.config/nim/config.nims:

seems like a separate bug... maybe file another bug for that?

[kaushalmodi]

remember to use permalinks instead of links to master

Thanks for pointing that out. I have now updated that link.

I always do that! Just forgot this time.

---

Update: I have now removed even that link.. you don't need that whole config.nims to reproduce this issue. Simply adding import os to config.nims is enough.

[kaushalmodi]

seems like a separate bug... maybe file another bug for that?

Done! #10031

[kaushalmodi]

Even if I skip my user config in the koch building step by doing ./bin/nim --skipUserCfg c koch, I get the same failure when koch is used to build the final nim binary:

km²~/downloads/:git/Nim> ./koch boot -d:release                 12/17 2:29pm
iteration: 1
compiler/nim0 c -d:release --nimcache:nimcache/r_linux_amd64 compiler/nim.nim
Hint: used config file '/home/kmodi/downloads/git/Nim/config/nim.cfg' [Conf]
Hint: used config file '/home/kmodi/downloads/git/Nim/compiler/nim.cfg' [Conf]
Hint: used config file '/home/kmodi/.config/nim/config.nims' [Conf]
../lib/system.nim(376, 50) Warning: unknown magic 'Destroy' might crash the compiler [UnknownMagic]
../lib/pure/os.nim(705, 14) Error: undeclared identifier: 'Stat'
FAILURE

[timotheecour]

confirmed the bug