From @masak

<masak> rakudo​: my ($found) = grep 1, 1..1_000_000; say 'alive'
<p6eval> rakudo 7b5b9d​: ( no output )
<masak> :/
<jnthn> That's...surprising.
<masak> is it worth an RT ticket?
<jnthn> masak​: It hangs at repl?
<jnthn> masak​: I think it should be lazy.
<jnthn> If it's not being then yes, imo.
* masak tries
<jnthn> (good to verify not just p6eval oddity)
<masak> yes, hangs at REPL.
* masak submits rakudobug

[...]

<masak> it even segfaulted :(
<masak> after a minute or so.
<arnsholt> OOM perhaps?
<jnthn> :-/
<masak> arnsholt​: likely, yes.
<arnsholt> Smells like someone forgot to check the return value of a malloc()

Found this example in A04, which promised it would be lazy.

If the lack of laziness is fixed, it'll likely be difficult to
reproduce the segfault. So perhaps the latter should be investigated
first. :)

From @pmichaud

Now fixed in 9993ee9. Assigning ticket to moritz++ for spectest coverage.

Pm

The RT System itself - Status changed from 'new' to 'open'

From @moritz

On Sun Jun 27 20​:04​:21 2010, pmichaud wrote​:

Now fixed in 9993ee9. Assigning ticket to moritz++ for spectest coverage.

Test coverage revealed that you only fixed the exact case mentioned in
the ticket, but moving the ($scalar) out of the declaration causes it to
loop still​:

./perl6 -e 'my ($x) = grep 5, 1..1_000_000; say $x'
5
./perl6 -e 'my $x; ($x) = grep 5, 1..1_000_000; say $x'
# takes *VERY* long

So giving ticket back to pmichaud++ for more general fix this time :-)

Cheers,
Moritz

From @kyleha

This is an automatically generated mail to inform you that tests are now available in t/spec/S03-operators/assign.t

commit 237f1992528d15f84b02d0f3bafdc4489096e5d5
Author​: moritz <moritz@​c213334d-75ef-0310-aa23-eaa082d1ae64>
Date​: Tue Jun 29 10​:00​:52 2010 +0000

  [t/spec] test for RT #​75950, my ($x) = grep $early_hit, @​long_range
 
  git-svn-id​: http://svn.pugscode.org/pugs@&#8203;31497 c213334d-75ef-0310-aa23-eaa082d1ae64

diff --git a/t/spec/S03-operators/assign.t b/t/spec/S03-operators/assign.t
index 829b37a..cbd6850 100644
--- a/t/spec/S03-operators/assign.t
+++ b/t/spec/S03-operators/assign.t
@@ -6,7 +6,7 @@ use Test;
 #                      V
 # L<S03/Changes to Perl 5 operators/list assignment operator now parses on the right>
 
-plan 240;
+plan 242;
 
 
 # tests various assignment styles
@@ -757,4 +757,13 @@ sub l () { 1, 2 };
     is((try {my $t = (1 == 0) ?? "true" !! "false"; $t}), "false", '.. also for false');
 }
 
+# RT #75950
+#?rakudo skip 'RT 75950'
+{
+    my $x;
+    lives_ok { ($x) = grep 5, 1..1_000_000 },
+            'Can grep lazily through a very long range';
+    is $x, 5, '... with correct result';
+}
+
 # vim: ft=perl6

From @moritz

works now, corrected test passes.

@moritz - Status changed from 'open' to 'resolved'