digitalmars.D.bugs - [Issue 4948] New: std.algorithm.sort asserts unexpectedly with certain comparators
- d-bugmail puremagic.com (33/33) Sep 26 2010 http://d.puremagic.com/issues/show_bug.cgi?id=4948
- d-bugmail puremagic.com (10/10) Jan 09 2011 http://d.puremagic.com/issues/show_bug.cgi?id=4948
- d-bugmail puremagic.com (11/11) Feb 06 2011 http://d.puremagic.com/issues/show_bug.cgi?id=4948
- d-bugmail puremagic.com (16/16) Apr 22 2012 http://d.puremagic.com/issues/show_bug.cgi?id=4948
- d-bugmail puremagic.com (11/11) Apr 22 2012 http://d.puremagic.com/issues/show_bug.cgi?id=4948
- d-bugmail puremagic.com (24/24) Apr 22 2012 http://d.puremagic.com/issues/show_bug.cgi?id=4948
- d-bugmail puremagic.com (9/9) Apr 22 2012 http://d.puremagic.com/issues/show_bug.cgi?id=4948
- d-bugmail puremagic.com (9/9) Apr 22 2012 http://d.puremagic.com/issues/show_bug.cgi?id=4948
- d-bugmail puremagic.com (9/9) Jun 10 2012 http://d.puremagic.com/issues/show_bug.cgi?id=4948
http://d.puremagic.com/issues/show_bug.cgi?id=4948 Summary: std.algorithm.sort asserts unexpectedly with certain comparators Product: D Version: D2 Platform: x86_64 OS/Version: Windows Status: NEW Severity: normal Priority: P2 Component: DMD AssignedTo: nobody puremagic.com ReportedBy: peter.alexander.au gmail.com 14:10:13 PDT --- The following code asserts unexpectedly when compiled with DMD 2.048 using no flags. void main() { alias Tuple!(int, "x", int, "y") V; V[] vs = [V(3, 4), V(6, 8)]; float arg(V v) { return atan2(cast(float)v.y, cast(float)v.x); } bool order(V a, V b) { return arg(a) < arg(b); } sort!order(vs); } core.exception.AssertError C:\D\dmd2\windows\bin\..\..\src\phobos\std\array.d(356): Attempting to fetch the front of an empty array It does not assert when the arg(V) function is replaced to be something more simple, and only asserts when vs has particular values. I suspect this has something to do with floating point inaccuracies with atan2, but haven't looked deep enough into the issue. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Sep 26 2010
http://d.puremagic.com/issues/show_bug.cgi?id=4948 Andrei Alexandrescu <andrei metalanguage.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|NEW |ASSIGNED CC| |andrei metalanguage.com AssignedTo|nobody puremagic.com |andrei metalanguage.com -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Jan 09 2011
http://d.puremagic.com/issues/show_bug.cgi?id=4948 Brad Roberts <braddr puremagic.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Platform|x86_64 |x86 --- Mass migration of bugs marked as x86-64 to just x86. The platform run on isn't what's relevant, it's if the app is a 32 or 64 bit app. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Feb 06 2011
http://d.puremagic.com/issues/show_bug.cgi?id=4948 SomeDude <lovelydear mailmetrash.com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |lovelydear mailmetrash.com PDT --- Note that replacing float arg(V v) { return atan2(cast(float)v.y , cast(float)v.x); } with float arg(V v) { return (cast(float)v.y * cast(float)v.x); } or float arg(V v) { return (cast(float)v.y / cast(float)v.x); } is enough to make the bug disappear... -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Apr 22 2012
http://d.puremagic.com/issues/show_bug.cgi?id=4948 Andrei Alexandrescu <andrei metalanguage.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|ASSIGNED |RESOLVED Resolution| |WORKSFORME 09:42:49 PDT --- Works for me on 2.059. I'll also note that arg(v[0]) == arg(v[1]). -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Apr 22 2012
http://d.puremagic.com/issues/show_bug.cgi?id=4948 SomeDude <lovelydear mailmetrash.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|RESOLVED |REOPENED Resolution|WORKSFORME | PDT --- I'm sorry but I'm reopening the case: there is no reason for the sort to fail if two elements are equal. A sort that fails in this case is broken. Besides, as I've said before, it works with a multiplication or a division, even with equals elements. It only fails with the atan2 function. import std.stdio; import std.typecons, std.algorithm, std.math; void main() { alias Tuple!(int, "x", int, "y") V; V[] vs = [V(6, 8), V(1, 2), V(6, 8), V(5,6)]; float arg(V v) { return (cast(float)v.y * cast(float)v.x); } bool order(V a, V b) { return arg(a) < arg(b); } writeln(sort!order(vs)); } -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Apr 22 2012
http://d.puremagic.com/issues/show_bug.cgi?id=4948 10:43:11 PDT --- I meant to say it works for me with no assert no nothing. For the last example the output is: Tuple!(int,"x",int,"y")(1, 2), Tuple!(int,"x",int,"y")(5, 6), Tuple!(int,"x",int,"y")(6, 8), Tuple!(int,"x",int,"y")(6, 8)] -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Apr 22 2012
http://d.puremagic.com/issues/show_bug.cgi?id=4948 10:49:24 PDT --- Rats. That's the output with the multiplication. Using atan2 the output is: [Tuple!(int,"x",int,"y")(5, 6), Tuple!(int,"x",int,"y")(6, 8), Tuple!(int,"x",int,"y")(6, 8), Tuple!(int,"x",int,"y")(1, 2)] That's on OSX Lion/64 bit. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Apr 22 2012
http://d.puremagic.com/issues/show_bug.cgi?id=4948 Andrei Alexandrescu <andrei metalanguage.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|REOPENED |RESOLVED Resolution| |WORKSFORME -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Jun 10 2012