Nim #head: sorting via reference hangs compiler

[skilchen]

The following test causes the Nim 0.17.3 compiler just cloned from github to hang. When i try nim c -r t1.nim the compilation produces an error message like:

t1.c: In function ‘test_BN7jJb30AIoqmGLz9c6zhkw’:
./nimcache/t1.c:297:51: error: ‘tyObject_Bar_jvMTkVWUjBFb12b6SKU1qg {aka > struct tyObject_Bar_jvMTkVWUjBFb12b6SKU1qg}’ has no member named ‘barLen_0’
sort_84EnBzTXl9c1maQcyvYsKBQ((*(x)).bar, ((*x)).barLen_0, T1_,
((tyEnum_SortOrder_8iBc6wlNqBa9cju9cUAhUAxA) 1));

and hangs.

On Windows the Nim version failing this test is:

Nim Compiler Version 0.17.3 (2017-11-12) [Windows: amd64]
Copyright (c) 2006-2017 by Andreas Rumpf

git hash: 22ceab0
active boot switches: -d:release

(On Windows the compiler doesn't hang as on Linux, but simply crashes.)

The same test passed on 0.17.2 (and on earlier versions of 0.17.3)

discard """
  output: @[0, 4, 9, 1, 3, 2]
@[0, 1, 2, 3, 9]
"""

import algorithm

type
  Bar = object
    bar: ref seq[int]
  Foo = ref Bar

proc test(x: ref Foo) =
  x.bar[].del(1)
  x.bar[].sort(cmp)

proc main() =
  var foo: ref Foo
  new(foo)

  var s = @[0, 4, 9, 1, 3, 2]

  var sr: ref seq[int]
  new(sr)
  sr[] = s

  foo[] = Foo(bar: sr)
  echo($foo.bar[])

  test(foo)
  echo($foo.bar[])

main()

[skilchen]

my first attempt at bisecting:

b407f083bafa227470caa077b2f70a6bc4da2dc3 is the first bad commit
commit b407f083bafa227470caa077b2f70a6bc4da2dc3
Author: Araq 
Date:   Tue Oct 24 09:40:28 2017 +0200

    destructors: work in progress

:040000 040000 0253fb2bb0d67a39d47a29ac41d4dc42fedb4f73 046678f702bca94d05ffe09e6028ffb569913bc2 M	compiler
:040000 040000 15808b10bdf8fb1c1d26f8a338bc1e56e022700f cbc8964b93ceb94f8d87243f639b7fcbdb712df0 M	lib
:040000 040000 f87f1a5fc1f5094352f01d8bd9a60428cd5fa3ef aefac571ad71cdd5a5e8c416d6e8802af01b7749 M	tests

The first bad commit translates my test to:

N_NIMCALL(void, test_BN7jJb30AIoqmGLz9c6zhkw)(tyObject_Bar_jvMTkVWUjBFb12b6SKU1qg** x) {
	tyProc_fDD7zVPPl59bNBu4ChTEQeQ T1_;
	nimfr_("test", "t1.nim");
	nimln_(14, "t1.nim");
	del_piMKKyQMYfDFMeykSxoPAg((*(*x)).bar, ((NI) 1));
	nimln_(15, "t1.nim");
	memset((void*)(&T1_), 0, sizeof(T1_));
	T1_.ClP_0 = ((TM_T8UX4uCLBe2k9c29b5ubzYSA_2) (cmp_8Eruo47qvrfENwO9aWPZfBQ_3)); T1_.ClE_0 = NIM_NIL;
	sort_84EnBzTXl9c1maQcyvYsKBQ((*(*x)).bar, (*(*x)).barLen_0, T1_, ((tyEnum_SortOrder_8iBc6wlNqBa9cju9cUAhUAxA) 1));
	popFrame();
}

and the last good commit to:

N_NIMCALL(void, test_BN7jJb30AIoqmGLz9c6zhkw)(tyObject_Bar_jvMTkVWUjBFb12b6SKU1qg** x) {
	tyProc_fDD7zVPPl59bNBu4ChTEQeQ T1_;
	nimfr_("test", "t1.nim");
	nimln_(14, "t1.nim");
	del_piMKKyQMYfDFMeykSxoPAg((*(*x)).bar, ((NI) 1));
	nimln_(15, "t1.nim");
	memset((void*)(&T1_), 0, sizeof(T1_));
	T1_.ClP_0 = ((TM_T8UX4uCLBe2k9c29b5ubzYSA_2) (cmp_8Eruo47qvrfENwO9aWPZfBQ_3)); T1_.ClE_0 = NIM_NIL;
	sort_84EnBzTXl9c1maQcyvYsKBQ((*(*(*x)).bar)->data, (*(*(*x)).bar)->Sup.len, T1_, ((tyEnum_SortOrder_8iBc6wlNqBa9cju9cUAhUAxA) 1));
	popFrame();
}

[skilchen]

thanks for the fix!