digitalmars.D.bugs - [Issue 704] New: destructors are called even if the constructor throws an exception
- d-bugmail puremagic.com (56/56) Dec 21 2006 http://d.puremagic.com/issues/show_bug.cgi?id=704
- d-bugmail puremagic.com (56/56) May 09 2007 http://d.puremagic.com/issues/show_bug.cgi?id=704
- d-bugmail puremagic.com (9/9) Oct 28 2007 http://d.puremagic.com/issues/show_bug.cgi?id=704
- d-bugmail puremagic.com (15/15) Jan 16 2009 http://d.puremagic.com/issues/show_bug.cgi?id=704
- d-bugmail puremagic.com (6/6) Jan 16 2009 http://d.puremagic.com/issues/show_bug.cgi?id=704
- d-bugmail puremagic.com (8/8) Jan 17 2009 http://d.puremagic.com/issues/show_bug.cgi?id=704
- d-bugmail puremagic.com (11/16) Nov 19 2011 http://d.puremagic.com/issues/show_bug.cgi?id=704
http://d.puremagic.com/issues/show_bug.cgi?id=704
Summary: destructors are called even if the constructor throws an
exception
Product: D
Version: 0.177
Platform: PC
OS/Version: Linux
Status: NEW
Severity: normal
Priority: P2
Component: DMD
AssignedTo: bugzilla digitalmars.com
ReportedBy: thomas-dloop kuehne.cn
(originally posted by Sean Kelly <sean f4.ca> on 2006-01-24 as
news:dr5uqg$2hn7$1 digitaldaemon.com)
// This demonstrates incorrect behavior for auto class
// construction. If an exception is thrown out of a
// class ctor then it is an incomplete object and its
// dtor should not be called.
import std.c.stdio;
auto class AutoClass
{
public:
this()
{
printf( "ctor\n" );
throw new Exception( "" );
}
~this()
{
printf( "dtor\n" );
}
}
void main()
{
try
{
auto AutoClass c = new AutoClass();
}
catch( Exception e )
{
printf( "caught\n" );
}
printf( "continue\n" );
}
C:\code\d\bugs>dmd 101_1.d
C:\bin\dmd\bin\..\..\dm\bin\link.exe 101_1,,,user32+kernel32/noi;
C:\code\d\bugs>101_1
ctor
caught
continue
dtor
test cases:
http://dstress.kuehne.cn/run/a/auto_14_A.d
http://dstress.kuehne.cn/run/a/auto_14_B.d
--
Dec 21 2006
d-bugmail puremagic.com
http://d.puremagic.com/issues/show_bug.cgi?id=704
braddr puremagic.com changed:
What |Removed |Added
----------------------------------------------------------------------------
Severity|normal |major
Retesting with a newest version of the compiler (1.014), these two tests should
probably be altered with s/auto/scope/ due to the changes in the language.
Also, throwing from a destructor is iffy behavior by itself. Either way, they
still hit the throw in the dtor.
However, fixing the throw from destructor issue like this:
1 module dstress.run.a.auto_14_A;
2
3 import std.stdio;
4
5 bool dtorcalled = false;
6
7 auto class MyClass{
8 this(){
9 writefln("in ctor");
10 throw new Exception("dummy");
11 }
12
13 ~this(){
14 writefln("in dtor");
15 dtorcalled = true;
16 }
17 }
18
19 int main(){
20 try{
21 auto MyClass c;
22 c = new MyClass();
23 }catch{}
24
25 if(!dtorcalled){
26 writefln("dtor not called");
27 return 0;
28 }else{
29 writefln("dtor called");
30 assert(0);
31 }
32
33 assert(0);
34 }
Results in:
in ctor
dtor not called
in dtor
So, there seems to be two issues here:
1) the dtor is being called at the wrong place, much after the scope it's
declared within has gone away.
2) it's being called at all due to the constructor exiting via throw.
Upgrading to severity major since I can't think of any work around and proper
scope behavior is a fairly important language feature.
--
May 09 2007
http://d.puremagic.com/issues/show_bug.cgi?id=704
bugzilla digitalmars.com changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|NEW |RESOLVED
Resolution| |WORKSFORME
Works in dmd 1.022 and 2.007.
--
Oct 28 2007
http://d.puremagic.com/issues/show_bug.cgi?id=704
gide nwawudu.com changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|RESOLVED |REOPENED
Resolution|WORKSFORME |
I noticed this issue in my code. I think the problem is that the following code
should not be allowed.
scope MyClass c; // or auto MyClass c;
c = new MyClass();
The following code works correctly.
scope MyClass c = new MyClass();
Maybe the tests should be changed in dstress.
--
Jan 16 2009
http://d.puremagic.com/issues/show_bug.cgi?id=704 I'm not sure whether it is a bug (unless specs specify other behavior). Unlike C++, objects in D are fully constructed /before/ entering ctor and thus I would expect the dtor to be called even if ctor throws. --
Jan 16 2009
http://d.puremagic.com/issues/show_bug.cgi?id=704 Default initializing object's fields doesn't mean full object construction. I do believe that an object should be considered constructed only if its constructor has completed successfully. Otherwise, the constructor should clean after itself and only deallocator (if any), but not destructor, should be run. Currently, deallocator is not run, meaning another bug in the compiler. --
Jan 17 2009
http://d.puremagic.com/issues/show_bug.cgi?id=704
Lionello Lunesu <lio+bugzilla lunesu.com> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |lio+bugzilla lunesu.com
23:16:05 PST ---
Default initializing object's fields doesn't mean full object construction. I
do believe that an object should be considered constructed only if its
constructor has completed successfully. Otherwise, the constructor should clean
after itself and only deallocator (if any), but not destructor, should be run.
Currently, deallocator is not run, meaning another bug in the compiler.
--
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
Nov 19 2011