Backport #7671

Unexpected result of the Flip-Flop

Added by Heesob Park about 2 years ago. Updated about 2 years ago.

[ruby-core:51296]
Status:Closed
Priority:Normal
Assignee:Usaku NAKAMURA

Description

Reported from http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-talk/402825

C:\work>irb
irb(main):001:0> vs = (1..9).to_a
=> [1, 2, 3, 4, 5, 6, 7, 8, 9]
irb(main):002:0> v1 = vs.select { |n| if n==3..n==6 then 1 end }
=> [3, 4, 5, 6]
irb(main):003:0> v2 = vs.select { |n| if n==2..n==16 then 1 end }
=> [2, 3, 4, 5, 6, 7, 8, 9]
irb(main):004:0> v3 = vs.select { |n| if n==3..n==6 then 1 end }
=> [1, 2, 3, 4, 5, 6]

v1 and v3 use some condition , return value is different.

This bug is due to changeset r38292 and only occurs on the irb session.

Here is a patch:
diff --git a/compile.c b/compile.c.new
index db060e7..e644390 100644
--- a/compile.c
+++ b/compile.c.new
@@ -5057,7 +5057,7 @@ iseq_compile_each(rb_iseq_t *iseq, LINK_ANCHOR *ret, NODE * node, int poped)

if (!data) data = iseq->compile_data;
cnt = data->flip_cnt++ + DEFAULT_SPECIAL_VAR_COUNT;
  • key = INT2FIX(cnt);
  • key = LL2NUM(cnt+(VALUE)iseq);

    ADD_INSN2(ret, nd_line(node), getspecial, key, INT2FIX(0));
    ADD_INSNL(ret, nd_line(node), branchif, lend);

Associated revisions

Revision 38739
Added by Nobuyoshi Nakada about 2 years ago

vm_core.h: flip_cnt in rb_iseq_t

  • vm_core.h (rb_iseq_t): move flip_cnt from struct iseq_compile_data, because it has same life span as enclosing iseq. [Bug #7671]

Revision 38781
Added by Usaku NAKAMURA about 2 years ago

merge revision(s) 38739: [Backport #7671]

* vm_core.h (rb_iseq_t): move flip_cnt from struct iseq_compile_data,
  because it has same life span as enclosing iseq.  [Bug #7671]
  

History

#1 Updated by Nobuyoshi Nakada about 2 years ago

  • Status changed from Open to Closed
  • % Done changed from 0 to 100

This issue was solved with changeset r38739.
Heesob, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.


vm_core.h: flip_cnt in rb_iseq_t

  • vm_core.h (rb_iseq_t): move flip_cnt from struct iseq_compile_data, because it has same life span as enclosing iseq. [Bug #7671]

#2 Updated by Nobuyoshi Nakada about 2 years ago

  • Tracker changed from Bug to Backport
  • Project changed from Ruby trunk to Backport193
  • Status changed from Closed to Assigned
  • Assignee set to Usaku NAKAMURA

#3 Updated by Usaku NAKAMURA about 2 years ago

  • Status changed from Assigned to Closed

This issue was solved with changeset r38781.
Heesob, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.


merge revision(s) 38739: [Backport #7671]

* vm_core.h (rb_iseq_t): move flip_cnt from struct iseq_compile_data,
  because it has same life span as enclosing iseq.  [Bug #7671]
  

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