[Bug c++/18192] New: Serious Performance Bug depending on a donothing destructor declaration

[Bug c++/18192] New: Serious Performance Bug depending on a donothing destructor declaration

[dkouroun at mailbox dot gr]

Dear GCC Team, 
I have experienced a serious performance bug 
with g++-3.4.2. In the attached code you can 
see the source code which is quite simple. In 
the file TypeDefinitions.h I use some typedef 
statements to be able play with different types. 
 
The problem is in file FiniteElementTypes.h!!! 
The one and only class in that file has a 
destructor declaration : 
 
public: 
  ~FiniteElement() {} 
 
When that destructor is commented out the program 
in my Sony-VAIO pentium4 2.66GHz needs almost 
4.450 seconds to run. When this destructor is not 
commented out the program needs 7.350 seconds to run. 
Even worse, when the destructor is not commented out 
and I change in TypeDefinitions.h the type Real from 
cRref to: 
 
typedef cR Real; 
 
the program needs 10.540 seconds to run. If I go to 
the file AsmExprOperators.h and having 
 
typedef cR Real; 
 
in Typedefinitions, I change all operators() from 
 
==>inline R operator()(indexType i, Real x, Real y, Real z) const 
 
to 
 
==>inline R operator()(indexType i, Real& x, Real& y, Real& z) const 
 
then the program again needs 7.300 seconds to run. 
 
Of course if I comment out the destructor declaration from the 
class FiniteElement then the program needs only 4.430 seconds to run. 
 
SuSE Linux 9.0 gcc-3.3.1 is insensitive to the destructor declaration 
but it needs almost 29.800 seconds! 
 
Intel ICC compiler though version 8.1.022 is also insensitive 
to the destructor declaration and it needs only 4.300 seconds!

-- 
           Summary: Serious Performance Bug depending on a donothing
                    destructor declaration
           Product: gcc
           Version: 3.4.2
            Status: UNCONFIRMED
          Severity: critical
          Priority: P2
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: dkouroun at mailbox dot gr
                CC: gcc-bugs at gcc dot gnu dot org
  GCC host triplet: SuSE 9.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18192

[Bug c++/18192] Serious Performance Bug depending on a donothing destructor declaration

[dkouroun at mailbox dot gr]

------- Additional Comments From dkouroun at mailbox dot gr  2004-10-28 10:34 -------
Created an attachment (id=7422)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=7422&action=view)
The source code


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18192

[Bug c++/18192] Serious Performance Bug depending on a donothing destructor declaration

[dkouroun at mailbox dot gr]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   GCC host triplet|SuSE 9.0                    |SuSE 9.2
            Version|3.4.2                       |3.4.3


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18192

[Bug c++/18192] Serious Performance Bug depending on a donothing destructor declaration

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-11-24 18:27 -------
This might have to do with execeptions.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|critical                    |normal
           Keywords|                            |missed-optimization


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18192

[Bug c++/18192] Serious Performance Bug depending on a donothing destructor declaration

[dkouroun at mailbox dot gr]

------- Additional Comments From dkouroun at mailbox dot gr  2004-11-25 10:04 -------
(In reply to comment #2) 
> This might have to do with execeptions. 
 
What kind of exceptions? For icc it doesn't make any difference whether or not 
you comment out that donothing destructor!!! g++-3.4.3 still has that problem! 
 
 

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18192

[Bug c++/18192] Serious Performance Bug depending on a donothing destructor declaration

[jason at gcc dot gnu dot org]

------- Additional Comments From jason at gcc dot gnu dot org  2005-09-15 19:18 -------
Please try GCC 4.  We're unlikely to work on tweaking the performance of the GCC
3.4 line.

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18192

[Bug c++/18192] Serious Performance Bug depending on a donothing destructor declaration

[jason at gcc dot gnu dot org]

------- Comment #5 from jason at gcc dot gnu dot org  2006-03-04 01:29 -------
Tested, bug not present in gcc 4.0.2.  Not going to fix in 3.x.


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jason at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |WONTFIX


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18192