[Coin-discuss] Bug Report in PackedVectorBase

[Laszlo Ladanyi]

I have moved things a bit around, now things should work with MSVC 2003 as
well.

--Laci

On Sun, 5 Oct 2003, Leo Lopes wrote:

> Hi Laszlo,
> 
>     I think I started my msg incorrectly, by even bringing up whether or 
> not compiler A or B was at fault. I apologize for that. The question you 
> brought up about how to deal with ANY compiler's bugs is an important 
> one. My 2c on that is to treat each situation individually. The argument 
> for that approach is that these days, almost always all that is required 
> are very simple changes. Furthermore, the result is often code 
> improvement, and sometimes when you are lucky even design improvements. 
> At least that has been my experience.
> 
>     For this particular issue, I agree with your solution. I think that 
> the binaryOp methods as they are now don't belong in PackedVectorBase. 
> My (strictly academic, I admit) simplest arguments for that are: a base 
> class should not have any knowledge about a derived class; and a method 
> should not be used in a file if it isn't defined in that file or in a 
> file included from that file.
> 
>     BTW, Kipp Martin tells me that with the changes I sent you COIN 
> compiles cleanly and works on MSVC 03.
> 
> 
> Cheers,
> Leo.
> 
> Laszlo Ladanyi wrote:
> 
> >Hi Leo,
> >
> >Actually, I believe that MSVC 2003 is at fault. The binaryOp methods are
> >templated methods and the compiler has no business in compiling them until it
> >knows the template arguments. What I think is that MSVC 2003 tries to be
> >clever and precompile those parts of the method that do not depend on the
> >template argument. But that's a problem with the compiler. Also, Sun's CC,
> >IBM's xlC, HP's aCC compile the code without any problems...
> >
> >This raises the issue of how do we deal with bugs in Microsoft's compilers?
> >(The question is valid regardless of whether MSVC 2003 is at fault now or
> >not.) To get wide audience, we need them to compile our code. But that would
> >be sort of letting the bully to win. (The bully's compiler is faster, but only
> >because it cheats on the rules, but we can't do anything about it, so we
> >conform...)
> >
> >In this particular case moving binatyOp into the PackedVector class is not the
> >right solution either. If we did that we couldn't use ShallowPackedVectors in
> >binaryOps.
> >
> >A possible solution would be to move binaryOp into CoinPackedVector.hpp as a
> >templated function (not a method in PackedVector. This actually makes sense,
> >after all, the does function return a PackedVector...
> >
> >What do people think? (On both questions.)
> >
> >--Laci
> >
> >On Sat, 4 Oct 2003, Leo Lopes wrote:
> >
> >  
> >
> >>Dear Laszlo,
> >>
> >>	I was having trouble compiling the basic COIN library under the newest 
> >>VS .net (I know, I know), and I noticed you were the last to update 
> >>CoinPackedVectorBase and CoinPackedVector. I'd like to point out a 
> >>feature of that code that is causing a problem. It is on lines 164, 182, 
> >>and 200, and the couple of lines following each case. MSVC 2003 
> >>complains about this code even though gcc and the previous MSVC don't, 
> >>and I think at least this time MSVC 2003 is right.
> >>
> >>	The problem is the following: when compiling PackedVectorBase, a 
> >>compiler has no way of knowing that PackedVector has a 
> >>setTestForDuplicateIndex method. It doesn't know, at this point, that 
> >>PackedVector is a child of PackedVectorBase. My guess is that the code 
> >>as it is now only works in gcc and the old MSVC because of the mechanism 
> >>that gcc and MSVC use to implement templates.
> >>
> >>	I changed PackedVectorBase and PackedVector so that any references to 
> >>PackedVector are removed from its parent, PackedVectorBase. This 
> >>involved moving the binaryOp functions to PackedVector and changing some 
> >>signatures. This allowed the Coin library ato compile cleanly under MSVC 
> >>and gcc and Clp to compile cleanly under gcc. I haven't tried other 
> >>libraries/compilers combinations yet.
> >>
> >>	The sources I am sending you are not changes of the absolute newest 
> >>versions in the CVS. However the same holds true of those versions.
> >>
> >>Cheers,
> >>Leo.
> >>
> >>Laszlo Ladanyi wrote:
> >>    
> >>
> >>>I think I caught all memory problems. At least now valgrind is quiet. It
> >>>wasn't too bad, various pointers got deleted multiple times. I think there are
> >>>memory leaks left. I'll try to deal with them over the weekend or early next
> >>>week.
> >>>
> >>>All the changes are committed. 
> >>>
> >>>Thanks for the bug report!
> >>>--Laci
> >>>
> >>>
> >>>_______________________________________________
> >>>Coin-discuss mailing list
> >>>Coin-discuss at www-124.ibm.com
> >>>http://www-124.ibm.com/developerworks/oss/mailman/listinfo/coin-discuss
> >>>      
> >>>
> >>-- 
> >>=======================================================================
> >>Leonardo B. Lopes                                   leo at sie.arizona.edu
> >>Visiting Assistant Professor                              (520)626-1780
> >>SIE - University of Arizona
> >>
> >>    
> >>
> >
> >  
> >
> 
> -- 
> =======================================================================
> Leonardo B. Lopes                                   leo at sie.arizona.edu 
> Visiting Assistant Professor                              (520)626-1780
> SIE - University of Arizona
> 
> 
>