digitalmars.D.bugs - [Issue 1841] New: Closure detection doesn't work when variable is used in a nested function
- d-bugmail puremagic.com (45/45) Feb 15 2008 http://d.puremagic.com/issues/show_bug.cgi?id=1841
- d-bugmail puremagic.com (4/4) Mar 31 2008 http://d.puremagic.com/issues/show_bug.cgi?id=1841
- d-bugmail puremagic.com (34/34) Jul 27 2010 http://d.puremagic.com/issues/show_bug.cgi?id=1841
- d-bugmail puremagic.com (6/6) Oct 19 2010 http://d.puremagic.com/issues/show_bug.cgi?id=1841
- d-bugmail puremagic.com (10/10) Mar 27 2012 http://d.puremagic.com/issues/show_bug.cgi?id=1841
- d-bugmail puremagic.com (10/10) Nov 12 2012 http://d.puremagic.com/issues/show_bug.cgi?id=1841
- d-bugmail puremagic.com (12/12) Nov 12 2012 http://d.puremagic.com/issues/show_bug.cgi?id=1841
- d-bugmail puremagic.com (13/13) Jan 24 2013 http://d.puremagic.com/issues/show_bug.cgi?id=1841
- d-bugmail puremagic.com (10/10) Jan 26 2013 http://d.puremagic.com/issues/show_bug.cgi?id=1841
- d-bugmail puremagic.com (11/11) Jan 27 2013 http://d.puremagic.com/issues/show_bug.cgi?id=1841
- d-bugmail puremagic.com (10/10) Jan 27 2013 http://d.puremagic.com/issues/show_bug.cgi?id=1841
- d-bugmail puremagic.com (10/10) Feb 01 2013 http://d.puremagic.com/issues/show_bug.cgi?id=1841
http://d.puremagic.com/issues/show_bug.cgi?id=1841
Summary: Closure detection doesn't work when variable is used in
a nested function
Product: D
Version: 2.010
Platform: PC
OS/Version: Linux
Status: NEW
Severity: normal
Priority: P2
Component: DMD
AssignedTo: bugzilla digitalmars.com
ReportedBy: webmaster villagersonline.com
The following function should allocate the variable "heap" on the heap since it
is referenced in a delegate. However, as you can tell from the output of the
program, it gets allocated on the stack instead.
CODE
import std.stdio;
void Foo(void delegate() ignored)
{
int stack;
int heap;
writefln("&stack=",&stack," &heap=",&heap);
writefln();
void nested_func()
{
heap = 1;
}
Foo(delegate void() { nested_func(); });
}
void main()
{
Foo(null);
}
END CODE
For comparison, if you modify the variable "heap" directly in the deletage
literal, instead of having the delegate literal call the nested function, then
"heap" is correctly allocated on the heap.
Interestingly, if you have *two* heap variables, one of which is modified
directly in the delegate literal, and the other of which is only modified
inside the nested function, then BOTH of the heap variables are on the heap.
This seems to indicate that the compiler is doing a "do I need any closures
here" pass, which has a bug, and then has a "build closures" pass, which works
correctly.
--
Feb 15 2008
d-bugmail puremagic.com http://d.puremagic.com/issues/show_bug.cgi?id=1841 This seems to work on dmd 2.012. Did dmd change? --
Mar 31 2008
http://d.puremagic.com/issues/show_bug.cgi?id=1841
Don <clugdbug yahoo.com.au> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |clugdbug yahoo.com.au
Here's a clearer test case. The second assert fails.
Closure detection works correctly if you change the delegate literal to:
return delegate int() { int x=heap; return nested_func(); };
---------------------
//import std.stdio;
int delegate() Foo()
{
int stack;
int heap=3;
// writeln("&stack=",&stack," &heap=",&heap);
int nested_func()
{
++heap;
return heap;
}
return delegate int() { return nested_func(); };
}
void main()
{
auto z = Foo();
auto p = Foo();
assert(z()==4); // OK
p();
assert(z()==5); // fails
}
--
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
Jul 27 2010
http://d.puremagic.com/issues/show_bug.cgi?id=1841 See also bug 1908, test case 5w, for another example. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Oct 19 2010
http://d.puremagic.com/issues/show_bug.cgi?id=1841
Don <clugdbug yahoo.com.au> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |xinok live.com
*** Issue 7766 has been marked as a duplicate of this issue. ***
--
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
Mar 27 2012
http://d.puremagic.com/issues/show_bug.cgi?id=1841
Denis Shelomovskij <verylonglogin.reg gmail.com> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |dpx.infinity gmail.com
13:42:26 MSK ---
*** Issue 7303 has been marked as a duplicate of this issue. ***
--
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
Nov 12 2012
http://d.puremagic.com/issues/show_bug.cgi?id=1841
Denis Shelomovskij <verylonglogin.reg gmail.com> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |verylonglogin.reg gmail.com
Platform|x86 |All
Version|2.010 |D2
OS/Version|Linux |All
Severity|normal |major
--
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
Nov 12 2012
http://d.puremagic.com/issues/show_bug.cgi?id=1841 The basic problem is that the existing closure detection only checks parents of nested functions. It should also check sibling nested functions. Ie, if one nested function f calls another nested function g, then if g needs a closure, then so does f. More complex cases are possible, such as where f calls g which calls h, f escapes, h uses closure variables but f and g don't. I have a fix for the original test case, still working on the more complex cases. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Jan 24 2013
http://d.puremagic.com/issues/show_bug.cgi?id=1841
Don <clugdbug yahoo.com.au> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |bdom.pub+deebugz gmail.com
*** Issue 2148 has been marked as a duplicate of this issue. ***
--
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
Jan 26 2013
http://d.puremagic.com/issues/show_bug.cgi?id=1841 Commit pushed to master at https://github.com/D-Programming-Language/dmd https://github.com/D-Programming-Language/dmd/commit/e5de59d30026fa5267541a928d67af1e8c06f922 Fix issue 1841 Closure detection fails in nested functions If an escaping function doesn't use any closure variables, but calls another nested function which does, it must be marked as needing a closure. This 'calling a sibling' case was missing. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Jan 27 2013
http://d.puremagic.com/issues/show_bug.cgi?id=1841
Walter Bright <bugzilla digitalmars.com> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|NEW |RESOLVED
CC| |bugzilla digitalmars.com
Resolution| |FIXED
--
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
Jan 27 2013
http://d.puremagic.com/issues/show_bug.cgi?id=1841
Don <clugdbug yahoo.com.au> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |edmccard verizon.net
*** Issue 7801 has been marked as a duplicate of this issue. ***
--
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
Feb 01 2013