[Bug c++/8057] [3.3/3.4 regression] Templates/non-templates and warnings about statements without effects

[Bug c++/8057] [3.3/3.4 regression] Templates/non-templates and warnings about statements without effects

[pinskia@physics.uc.edu]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=8057


pinskia@physics.uc.edu changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |3.3.1

[Bug c++/8057] [3.3/3.4 regression] Templates/non-templates and warnings about statements without effects

[giovannibajo@libero.it]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=8057


giovannibajo@libero.it changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned@gcc.gnu.org      |gdr@gcc.gnu.org


------- Additional Comments From giovannibajo@libero.it  2003-06-09 15:54 -------
Assigned to diagnostic mantainer.

[Bug c++/8057] [3.3/3.4 regression] Templates/non-templates and warnings about statements without effects

[gdr at gcc dot gnu dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=8057


gdr at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |mark at codesourcery dot com
         AssignedTo|gdr at gcc dot gnu dot org  |unassigned at gcc dot gnu
                   |                            |dot org
             Status|NEW                         |ASSIGNED


------- Additional Comments From gdr at gcc dot gnu dot org  2003-07-07 16:04 -------
This PR has nothing to do with diagnostics per se.  The diagnostic thing is just
a symptom of a much fuhndamental desease: It has to do with function cloning and
inlining. More specifically, the double emission of diagnostic is due to the
fact that the constructor is cloned, hence its body is expanded twice.
The absence of diagnostic in Z::Z() is due to the fact that it is an inline
function and starting from some GCC-3.x, an inline function is defined (hence
its body expanded) only if used. To see what I mean, make the definition of
Z::Z() a non-inline function and you'll see the warning.
If you add the following

    struct A {
       void f();
    }; 

    void
    A::f() { Y::i; }

you'll see that the diagnostic is emitted only once.

So, this issue has nothing to do with templates per se.  It all has to do with
cloning and inlining.  So I'll hand it off.

[Bug c++/8057] [3.3/3.4 regression] Templates/non-templates and warnings about statements without effects

[pinskia at physics dot uc dot edu]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=8057


pinskia at physics dot uc dot edu changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |NEW

[Bug c++/8057] [3.3/3.4 regression] Templates/non-templates and warnings about statements without effects

[mmitchel at gcc dot gnu dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=8057


mmitchel at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|3.3.1                       |3.4


------- Additional Comments From mmitchel at gcc dot gnu dot org  2003-07-10 06:44 -------
Actually, the real problem here is that we use the middle-end to issue
diagnostics that need to be emitted from the front end.  I've sermonized on this
before: the idea of using the optimizers to detect unused/uninitialized/etc.
variables *sounds* good -- but it leads to all these very real usability
problems, which is why no other compiler does it this way.  There is nothing
that can be done to fix this problem with our current infrastructure, so this is
going to have to wait until (at least) GCC 3.4.

[Bug c++/8057] [3.3/3.4 regression] Templates/non-templates and warnings about statements without effects

[pinskia at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |minor


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=8057

[Bug c++/8057] [3.3/3.4 regression] Templates/non-templates and warnings about statements without effects

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-01-10 23:21 -------
This is regression from 2.95.3 so moving to 3.4.1 and this should not block the branch.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|3.4.0                       |3.4.1


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=8057

[Bug c++/8057] [3.3/3.4 regression] Templates/non-templates and warnings about statements without effects

[steven at gcc dot gnu dot org]

------- Additional Comments From steven at gcc dot gnu dot org  2004-01-12 23:39 -------
Move back the target for all regressions from 3.4.1 to 3.4.0, as required by 
our bug management policy. 

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|3.4.1                       |3.4.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=8057

[Bug c++/8057] [3.3/3.4/3.5 regression] Templates/non-templates and warnings about statements without effects

[mmitchel at gcc dot gnu dot org]

------- Additional Comments From mmitchel at gcc dot gnu dot org  2004-01-31 03:09 -------
My comments about lack of infrastructure for fixing this bug still apply.

Postponing until at least GCC 3.5.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|3.4.0                       |3.5.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=8057

[Bug c++/8057] [3.3/3.4/4.0 regression] Templates/non-templates and warnings about statements without effects

[mmitchel at gcc dot gnu dot org]

------- Additional Comments From mmitchel at gcc dot gnu dot org  2004-12-22 04:58 -------
We still have no viable mechanism for fixing this bug.  Postponing until GCC 4.1.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.0.0                       |4.1.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=8057