#14826: Eliminate build warning #809 regarding exceptions in virtual destructors of
STL base classes, with MSVC 2012/11.0 + ICC 13.0.1
--------------------------------------------------------------------------- -------------------------------+
Reporter: ghostvoodooman | Owner: Type: build error | Status: new
Priority: low | Milestone: Component: build | Version: 2.9-svn
Keywords: ICC Intel compiler visual studio 2012 virtual destructor throw exception warning 809 STL std | Blockedby: Patch: 1 | Blocking: --------------------------------------------------------------------------- -------------------------------+
I hope this is not a dupe.
I have 2 warnings in program using headers from wx, and some warnings when
building the whole wx library from the latest trunk.
In both projects I am using ICC 13.0.1 and STL from MSVC 2012 / 11.0 . I
am compiling wxWidgets as DLL|Debug|x64 and DLL|Release|x64 and using
enabled C++0x mode.
Though I guess it has nothing to do with ICC, since ICC plug-in in
MSVC/devenv.exe IDE is using MSVC's STL.
my custom setup.h (only relevant settings):
wxUSE_STL defined to 0
wxUSE_STD_CONTAINERS defined to 1
wxUSE_STD_IOSTREAM defined to 1
wxUSE_STD_DEFAULT defined to 1
wxUSE_STD_STRING defined to wxUSE_STD_DEFAULT
wxUSE_STD_STRING_CONV_IN_WXSTRING defined to wxUSE_STL
SVN trunk r72949 .
my program using WX library:
{{{
c:\PATH_TO_wxWidgets\include\wx/textctrl.h(682): warning #809: exception
specification for virtual function "wxTextCtrlBase::~wxTextCtrlBase" is
incompatible with that of overridden function "std::basic_streambuf<_Elem,
_Traits>::~basic_streambuf [with _Elem=char,
_Traits=std::char_traits<char>]"
c:\PATH_TO_wxWidgets\include\wx/msw/textctrl.h(34): warning #809:
exception specification for virtual function "wxTextCtrl::~wxTextCtrl" is
incompatible with that of overridden function "std::basic_streambuf<_Elem,
_Traits>::~basic_streambuf [with _Elem=char,
_Traits=std::char_traits<char>]"
}}}
wx library itself (this is only sort'ed and uniq'ued list):
{{{
..\..\include\wx/msw/textctrl.h(34): warning #809: exception specification
for virtual function "wxTextCtrl::~wxTextCtrl" is incompatible with that
of overridden function "std::basic_streambuf<_Elem,
_Traits>::~basic_streambuf [with _Elem=char,
_Traits=std::char_traits<char>]"
..\..\include\wx/stdstream.h(115): warning #809: exception specification
for virtual function "wxStdOutputStream::~wxStdOutputStream" is
incompatible with that of overridden function "std::basic_ios<_Elem,
_Traits>::~basic_ios [with _Elem=char, _Traits=std::char_traits<char>]"
..\..\include\wx/stdstream.h(115): warning #809: exception specification
for virtual function "wxStdOutputStream::~wxStdOutputStream" is
incompatible with that of overridden function "std::basic_ostream<_Elem,
_Traits>::~basic_ostream [with _Elem=char,
_Traits=std::char_traits<char>]"
..\..\include\wx/stdstream.h(115): warning #809: exception specification
for virtual function "wxStdOutputStream::~wxStdOutputStream" is
incompatible with that of overridden function "std::ios_base::~ios_base"
..\..\include\wx/stdstream.h(31): warning #809: exception specification
for virtual function "wxStdInputStreamBuffer::~wxStdInputStreamBuffer" is
incompatible with that of overridden function "std::basic_streambuf<_Elem,
_Traits>::~basic_streambuf [with _Elem=char,
_Traits=std::char_traits<char>]"
..\..\include\wx/stdstream.h(74): warning #809: exception specification
for virtual function "wxStdInputStream::~wxStdInputStream" is incompatible
with that of overridden function "std::basic_ios<_Elem,
_Traits>::~basic_ios [with _Elem=char, _Traits=std::char_traits<char>]"
..\..\include\wx/stdstream.h(74): warning #809: exception specification
for virtual function "wxStdInputStream::~wxStdInputStream" is incompatible
with that of overridden function "std::basic_istream<_Elem,
_Traits>::~basic_istream [with _Elem=char,
_Traits=std::char_traits<char>]"
..\..\include\wx/stdstream.h(74): warning #809: exception specification
for virtual function "wxStdInputStream::~wxStdInputStream" is incompatible
with that of overridden function "std::ios_base::~ios_base"
..\..\include\wx/stdstream.h(88): warning #809: exception specification
for virtual function "wxStdOutputStreamBuffer::~wxStdOutputStreamBuffer"
is incompatible with that of overridden function
"std::basic_streambuf<_Elem, _Traits>::~basic_streambuf [with _Elem=char,
_Traits=std::char_traits<char>]"
..\..\include\wx/textctrl.h(682): warning #809: exception specification
for virtual function "wxTextCtrlBase::~wxTextCtrlBase" is incompatible
with that of overridden function "std::basic_streambuf<_Elem,
_Traits>::~basic_streambuf [with _Elem=char,
_Traits=std::char_traits<char>]"
..\..\src\common\combocmn.cpp(943): warning #809: exception specification
for virtual function "wxComboCtrlTextCtrl::~wxComboCtrlTextCtrl" is
incompatible with that of overridden function "std::basic_streambuf<_Elem,
_Traits>::~basic_streambuf [with _Elem=char,
_Traits=std::char_traits<char>]"
..\..\src\generic\spinctlg.cpp(80): warning #809: exception specification
for virtual function "wxSpinCtrlTextGeneric::~wxSpinCtrlTextGeneric" is
incompatible with that of overridden function "std::basic_streambuf<_Elem,
_Traits>::~basic_streambuf [with _Elem=char,
_Traits=std::char_traits<char>]"
}}}
My best guess is that these WX classes are derived from STL classes (e.g.
streams) which might throw an exception in their virtual destructor.
Attaching patch fixing those warnings against r72949 , but I'm not sure
about it, it might cause performance penalty (due to exceptions) in build
without using STD/STL by custom setup.h . I guess there should be
preprocessor guards/disablers around "throw()" in my patch for such case?
Discussion subject changed to "#14826: Add wxNOEXCEPT and use it for std::streambuf-derived classes dtors (was: Eliminate build warning #809 regarding exceptions in virtual destructors of STL base classes, with MSVC 2012/11.0 + ICC 13.0.1)" by wxTrac
Subject: Re: #14826: Add wxNOEXCEPT and use it for std::streambuf-derived classes dtors (was: Eliminate build warning #809 regarding exceptions in virtual destructors of STL base classes, with MSVC 2012/11.0 + ICC 13.0.1)
`throw()` is deprecated in C++11, it doesn't seem like a good idea to
start adding it now. And, of course, C++11 `noexcept` is not widely
supported yet. So we probably need to define `wxNOEXCEPT` macro or
something like this and use it instead.
This being said, the warnings are perfectly harmless because you're never
going to delete a `wxTextCtrl` via `streambuf` pointer anyhow so it's
hardly high priority.
#14826: Add wxNOEXCEPT and use it for std::streambuf-derived classes dtors
--------------------------------------------------------------------------- -------------------------------+
Reporter: ghostvoodooman | Owner: Type: build error | Status: new
Priority: low | Milestone: Component: build | Version: 2.9-svn
Keywords: ICC Intel compiler visual studio 2012 virtual destructor throw exception warning 809 STL std | Blockedby: Patch: 1 | Blocking: --------------------------------------------------------------------------- -------------------------------+
Changes (by ghostvoodooman):
* status: infoneeded_new => new
Comment:
PS: and I am very sorry for my English spelling, I wrote it after I just
woke up, and I am not native speaker... But I hope everyone is able to
understand...
#14826: Add wxNOEXCEPT and use it for std::streambuf-derived classes dtors
--------------------------------------------------------------------------- -------------------------------+
Reporter: ghostvoodooman | Owner: Type: build error | Status: new
Priority: low | Milestone: Component: build | Version: 2.9-svn
Keywords: ICC Intel compiler visual studio 2012 virtual destructor throw exception warning 809 STL std | Blockedby: Patch: 1 | Blocking: --------------------------------------------------------------------------- -------------------------------+
Comment(by ghostvoodooman):
After searching some internets, I have found that C++0x compilers require
`throw()` but all compilers are able to understand `noexcept` not
regarding version of C++. Should we change this decoration by preprocessor
for some compiler that do not understands `noexcept`? Are there any?
There is my third version of patch, which compiles fine under MSVC2012 +
ICC 13.0.1 .
#14826: Add wxNOEXCEPT and use it for std::streambuf-derived classes dtors
--------------------------------------------------------------------------- -------------------------------+
Reporter: ghostvoodooman | Owner: Type: build error | Status: new
Priority: low | Milestone: Component: build | Version: 2.9-svn
Keywords: ICC Intel compiler visual studio 2012 virtual destructor throw exception warning 809 STL std | Blockedby: Patch: 1 | Blocking: --------------------------------------------------------------------------- -------------------------------+
Comment(by vadz):
Replying to [comment:4 ghostvoodooman]:
> After searching some internets, I have found that C++0x compilers
require `throw()` but all compilers are able to understand `noexcept` not
regarding version of C++.
This can't be right. `noexcept` is new in C++11, old compilers definitely
don't support it.
#14826: Add wxNOEXCEPT and use it for std::streambuf-derived classes dtors
--------------------------------------------------------------------------- -------------------------------+
Reporter: ghostvoodooman | Owner: Type: build error | Status: new
Priority: low | Milestone: Component: build | Version: 2.9-svn
Keywords: ICC Intel compiler visual studio 2012 virtual destructor throw exception warning 809 STL std | Blockedby: Patch: 1 | Blocking: --------------------------------------------------------------------------- -------------------------------+
Comment(by ghostvoodooman):
I was thinking about this, the base class's destructor could throw an
exception (in a rare situation), I think whether we should honour this
fact by using {{{ throw(...) }}} or, for higher versions of C++ "may-
throw" {{{ noexcept(false) }}}. If so, then macro should have a different
name. What do you think?
#14826: Add wxNOEXCEPT and use it for std::streambuf-derived classes dtors
--------------------------------------------------------------------------- -------------------------------+
Reporter: ghostvoodooman | Owner: Type: build error | Status: new
Priority: low | Milestone: Component: build | Version: 2.9-svn
Keywords: ICC Intel compiler visual studio 2012 virtual destructor throw exception warning 809 STL std | Blockedby: Patch: 1 | Blocking: --------------------------------------------------------------------------- -------------------------------+
Comment(by ghostvoodooman):
Replying to [comment:6 ghostvoodooman]:
> I was thinking about this, the base class's destructor could throw an
exception (in a rare situation), I think whether we should honour this
fact by using {{{ throw(...) }}} or, for higher versions of C++ "may-
throw" {{{ noexcept(false) }}}. If so, then macro should have a different
name. What do you think?
Please disregard my previous post, I have just found {{{ throw(...) }}}
produces the same warning.
Attaching my 4th version of patch ( warning_809_patch4.patch ).
#14826: Add wxNOEXCEPT and use it for std::streambuf-derived classes dtors
--------------------------------------------------------------------------- -------------------------------+
Reporter: ghostvoodooman | Owner: Type: build error | Status: new
Priority: low | Milestone: Component: build | Version: 2.9-svn
Keywords: ICC Intel compiler visual studio 2012 virtual destructor throw exception warning 809 STL std | Blockedby: Patch: 1 | Blocking: --------------------------------------------------------------------------- -------------------------------+
Comment(by vadz):
I'm confused about the comments in your macro definitions (clearly
`199711` corresponds to C++98, not C++0x...) but the patch itself is
probably still correct so I'll commit it soon, thanks.
(In [72978]) Add wxNOEXCEPT and use it for std::streambuf-derived classes.
This fixes warnings from Intel compiler about overriding function using a
different exception specification than the base one and also incidentally
provides a handy macro that can be useful in other situations.
(In [72984]) Add wxNOEXCEPT to all wxTextCtrl dtors.
Fix compilation with some compilers after r72978 which added wxNOEXCEPT to
wxTextCtrlBase dtor and wxTextCtrl dtor in wxMSW but not in all the other
ports.
Replying to [comment:10 VZ]:
> (In [72984]) Add wxNOEXCEPT to all wxTextCtrl dtors.
>
> Fix compilation with some compilers after r72978 which added wxNOEXCEPT
to
> wxTextCtrlBase dtor and wxTextCtrl dtor in wxMSW but not in all the
other
> ports.
>
> See #14826.
I was not sure what to do about compilation error on `wxGTK` port reported
in wx-dev list. This (above) was one approach. There is still problem if
one (an user) derives a new class from `wxTextCtrl[Base]`, since exception
specification will get propagated to sub class's dtor (e.g. to implement
custom auto-completition). So the user will be surprised about compile
error, like that one in the list.
Another approach (but rather ugly) would be to use the preprocessor to
enable/disable USAGE of `wxNOEXCEPT` in all (so far) dtors we use it now,
and (future) places as well. Like:
{{{
~foo()
#ifdef wxMSW
wxNOEXCEPT
#endif
{ }
}}}
(In [72989]) More compilation fixes after wxNOEXCEPT introduction.
This is a temporary change, r72984 and the following changes (see #14826)
will
probably be reverted soon anyhow, but for now at least fix wxGTK
compilation.
Replying to [comment:11 ghostvoodooman]:
> Another approach (but rather ugly) would be to use the preprocessor to
enable/disable USAGE of `wxNOEXCEPT` in all (so far) dtors we use it now,
and (future) places as well. Like:
> {{{
> ~foo()
> #ifdef wxMSW
> wxNOEXCEPT
> #endif
> { }
> }}}
I don't understand at all what does this solve, whether test for
`__WXMSW__` or `__INTELC__`. You'd still need to use `throw()` for your
own dtors.
IOW I don't see any solution preserving backwards compatibility at all
actually, not even a bad one.
I'll think about it a bit more but if I don't find anything new I'll
revert all these commits tomorrow.
#14826: Add wxNOEXCEPT and use it for std::streambuf-derived classes dtors
-----------------------------+--------------------------------------------- -
Reporter: ghostvoodooman | Owner:
Type: build error | Status: reopened
Priority: normal | Milestone: 2.9.5 Component: build | Version: 2.9-svn Resolution: | Keywords: ICC Intel compiler visual studio 2012 virtual destructor throw exception warning 809 STL std
Blockedby: | Patch: 1 Blocking: |
-----------------------------+--------------------------------------------- -
Changes (by ghostvoodooman):
* priority: low => normal
Comment:
As per our conversation in wx-dev list, I am attaching
`warning_809_patch5.patch` patch against r72991 , which disables ICC
13.0.1 warnings in C++0x mode about inconsistency of exception
specification of our virtual dtors when we are deriving classes from MSVC
2012's STL's ones.
Also, remove our macro `wxNOEXCEPT` from these dtors (fixing compile
errors with GCC).
Discussion subject changed to "#14826: Fix ICC warnings about std::streambuf-derived classes dtors (was: Add wxNOEXCEPT and use it for std::streambuf-derived classes dtors)" by wxTrac
Subject: Re: #14826: Fix ICC warnings about std::streambuf-derived classes dtors (was: Add wxNOEXCEPT and use it for std::streambuf-derived classes dtors)
I hoped it would be enough to use the pragmas in the header... If we
really need them in all source files deriving classes from `wxTextCtrl`,
it's a bad solution IMO and I'm pretty sure that nobody will add this
stuff around the next `wxTextCtrl`-derived class we add.
So for now I'll just revert all changes and I think the best way to fix
this would be to disable this warning globally for ICC in `wx/defs.h`.
Replying to [comment:16 vadz]:
> I hoped it would be enough to use the pragmas in the header... If we
really need them in all source files deriving classes from `wxTextCtrl`,
it's a bad solution IMO and I'm pretty sure that nobody will add this
stuff around the next `wxTextCtrl`-derived class we add.
That would mean user will not get this warning in their own code, if they
don't explicitly re-enable this warning after inclusion of all WX headers.
(In [72993]) Revert all wxNOEXCEPT-related changes.
This reverts r72978, 72984, 72989 and 72992. Do not use wxNOEXCEPT for
wxTextCtrl dtor as this breaks compilation of any user-defined classes
inheriting from it unless they use wxNOEXCEPT as well and the benefits
(fixing a harmless warning for the niche ICC compiler) are just not worth
the compatibility breakage.
