Re: [gentoo-dev] Re: RFC: News item regarding c++98 vs c++11

2014-10-24 Thread Anthony G. Basile 

HI everyone,

I've update the c++ news item for your consideration.  I incorporated 
suggestions, in particular a note about incompatibility between c++11 
compiled with different version of gcc differing in minor number (eg 4.7 
and 4.8).



--
Anthony G. Basile, Ph. D.
Chair of Information Technology
D'Youville College
Buffalo, NY 14201
(716) 829-8197
Title: GCC 4.7 Introduces New c++11 ABI 
Author: Anthony G. Basile 
Content-Type: text/plain
Posted: 2014-10-20
Revision: 1
News-Item-Format: 1.0
Display-If-Installed: >=sys-devel/gcc-4.7.0
Display-If-Keyword: amd64
Display-If-Keyword: arm
Display-If-Keyword: mips
Display-If-Keyword: ppc
Display-If-Keyword: ppc64
Display-If-Keyword: x86
Display-If-Keyword: amd64-fbsd
Display-If-Keyword: x86-fbsd

GCC 4.7 introduced the new experimental 2011 ISO C++ standard [1], along with
its GNU variant.  This new standard is not the default in GCC 4.7, 4.8 or 4.9,
the default is still gnu++98, but it can be enabled by passing -std=c++11 or
-std=gnu++11 to CXXFLAGS.

Users that wish to try c++11 should exercise caution because it is not
ABI-compatible with c++98.  Nor is c++11 code compiled with gcc-4.7 
ABI-compatible
with c++11 compiled with 4.8, and vice versa.  Thus linking c++98 and c++11, or
c++11 compiled with different versions of gcc, is likely to cause breakage.  For
packages which are self-contained or do not link against any libraries written
in C++, there is no problem.  However, switching to c++11 and then building
packages which link against any of the numerous libraries in an incompatible
ABI can lead to a broken system.

This is a precautionary news item and the typical user need not do anything.
However, as c++11 gains in popularity and the number of packages using it
increase, it is important that users understand these issues.

For an ABI compliance checker, and more information about C++ ABIs, see [2].  

Ref.
[1] http://www.stroustrup.com/C++11FAQ.html
[2] http://ispras.linuxbase.org/index.php/ABI_compliance_checker

Re: [gentoo-dev] Re: RFC: News item regarding c++98 vs c++11

2014-10-24 Thread Alex Xu 
On 24/10/14 10:31 AM, Anthony G. Basile wrote:
> HI everyone,
> 
> I've update the c++ news item for your consideration.  I incorporated
> suggestions, in particular a note about incompatibility between c++11
> compiled with different version of gcc differing in minor number (eg 4.7
> and 4.8).
> 
> 
lgtm. also mime attachments are hard to comment on.



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Re: [gentoo-dev] Re: RFC: News item regarding c++98 vs c++11

2014-10-24 Thread Paweł Hajdan, Jr. 
On 10/24/14 4:31 PM, Anthony G. Basile wrote:
> I've update the c++ news item for your consideration.  I incorporated
> suggestions, in particular a note about incompatibility between c++11
> compiled with different version of gcc differing in minor number (eg 4.7
> and 4.8).

Thanks, I think this is an improvement.

I'd still prefer an explicit mention that having gcc-4.7 and 4.8
installed simultaneously leads to known breakages, especially if 4.7 is
the active gcc version. The text of the news item implies this, but it's
just not obvious.

Also consider explicitly mentioning
. Obviously this
wouldn't be a complete list of issues, but from the CC list it's a
pretty common bug.

If in doubt, consider this question: what would be bad about including
the info I suggested above?

Paweł

> Title: GCC 4.7 Introduces New c++11 ABI 
> Author: Anthony G. Basile 
> Content-Type: text/plain
> Posted: 2014-10-20
> Revision: 1
> News-Item-Format: 1.0
> Display-If-Installed: >=sys-devel/gcc-4.7.0
> Display-If-Keyword: amd64
> Display-If-Keyword: arm
> Display-If-Keyword: mips
> Display-If-Keyword: ppc
> Display-If-Keyword: ppc64
> Display-If-Keyword: x86
> Display-If-Keyword: amd64-fbsd
> Display-If-Keyword: x86-fbsd
> 
> GCC 4.7 introduced the new experimental 2011 ISO C++ standard [1], along with
> its GNU variant.  This new standard is not the default in GCC 4.7, 4.8 or 4.9,
> the default is still gnu++98, but it can be enabled by passing -std=c++11 or
> -std=gnu++11 to CXXFLAGS.
> 
> Users that wish to try c++11 should exercise caution because it is not
> ABI-compatible with c++98.  Nor is c++11 code compiled with gcc-4.7 
> ABI-compatible
> with c++11 compiled with 4.8, and vice versa.  Thus linking c++98 and c++11, 
> or
> c++11 compiled with different versions of gcc, is likely to cause breakage.  
> For
> packages which are self-contained or do not link against any libraries written
> in C++, there is no problem.  However, switching to c++11 and then building
> packages which link against any of the numerous libraries in an incompatible
> ABI can lead to a broken system.
> 
> This is a precautionary news item and the typical user need not do anything.
> However, as c++11 gains in popularity and the number of packages using it
> increase, it is important that users understand these issues.
> 
> For an ABI compliance checker, and more information about C++ ABIs, see [2].  
> 
> Ref.
> [1] http://www.stroustrup.com/C++11FAQ.html
> [2] http://ispras.linuxbase.org/index.php/ABI_compliance_checker
> 




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[gentoo-dev] status of bugs blocking gcc-4.8.3

2014-10-24 Thread Anthony G. Basile 

Hi everyone,

Regarding blockers against bug  #461954 "(gcc-4.8) GCC 4.8 porting" and  
bug #516152 "(gcc-4.8-stable) sys-devel/gcc-4.8.? stabilization" here is 
the current situation:


bug #516548 - (PR61538) broken atomic on MIPS R1
-> As far as I can tell, this only effects R1.  It does not effect 
the fulong or longson (lemote netbooks), nor some other router boards i 
have.


bug #503838 - (PR60465) sys-libs/glibc: building w/gcc-4.8 crashes early 
on ia64

-> This effects only ia64.

bug #500064 - app-emulation/virtualbox-4.3.6 fails to build with gcc 
4.8.x in bundled iPXE

-> Poly-C wants to stabilize these along side gcc-4.8.

bug #465268 - dev-embedded/msp430-gcc-4.6.3_p20120406 with gcc-4.8.0
-> This is working with gcc-4.9 and doesn't need to hold up 4.8.

bug 458706 - PaX: Max. per-task virtual memory too small for llvm asan 
and gcc-4.8 asan
-> AddressSanitizer doesn't work with a PaX hardened kernel. Nor does it 
work on several arches nor on musl.  vapier has done some masking here.


bug 513386 - net-libs/webkit-gtk-2.4.3 - ./.libs/libwebkitgtk-3.0.so: 
undefined reference to `_ZNSt6chrono12steady_clock3nowEv@GLIBCXX_3.4.17'
-> This is a problem.  It relates to abi mismatching with libstdc++.  
The bug details how you can hit it in gentoo. Martin von Gagern pushed 
the issue upstream and pretty much got the answer "we're on our own"  So 
we'll have to deal with this as we go forward.

Seehttps://gcc.gnu.org/bugzilla/show_bug.cgi?id=61758

So except for some minor arch issue and bug 513386, which we're going to 
have to deal with for a while, gcc-4.8.3 looks good.  I went ahead and 
stabilized it on ppc and ppc64.  Its also stable on arm and hppa.  I 
don't want to speak for any other arch teams, but it may be time.


--
Anthony G. Basile, Ph.D.
Gentoo Linux Developer [Hardened]
E-Mail: bluen...@gentoo.org
GnuPG FP  : 1FED FAD9 D82C 52A5 3BAB  DC79 9384 FA6E F52D 4BBA
GnuPG ID  : F52D4BBA

Re: [gentoo-dev] Re: RFC: News item regarding c++98 vs c++11

2014-10-24 Thread Anthony G. Basile 

On 10/24/14 11:31, "Paweł Hajdan, Jr." wrote:

On 10/24/14 4:31 PM, Anthony G. Basile wrote:

I've update the c++ news item for your consideration.  I incorporated
suggestions, in particular a note about incompatibility between c++11
compiled with different version of gcc differing in minor number (eg 4.7
and 4.8).


Thanks, I think this is an improvement.

I'd still prefer an explicit mention that having gcc-4.7 and 4.8
installed simultaneously leads to known breakages, especially if 4.7 is
the active gcc version. The text of the news item implies this, but it's
just not obvious.

Also consider explicitly mentioning
. Obviously this
wouldn't be a complete list of issues, but from the CC list it's a
pretty common bug.



I agree, this bug is an example of the issues we'll have to face moving 
forward with 4.8/4.9 and c++.  I can reference it.



If in doubt, consider this question: what would be bad about including
the info I suggested above?


You don't need to convince me.  Its a good example.  There's no 
particular reason I didn't mention it.




Paweł



So I don't have to keep email the entire item to the list, how about 
just adding it as follows:


"Nor is c++11 code compiled with gcc-4.7 ABI-compatible with c++11 
compiled with 4.8, and vice versa.  An example can be see in ref. [2]"


Ref.
[2] https://bugs.gentoo.org/show_bug.cgi?id=513386


--
Anthony G. Basile, Ph. D.
Chair of Information Technology
D'Youville College
Buffalo, NY 14201
(716) 829-8197

[gentoo-dev] last rites: dev-perl/SVN-Mirror

2014-10-24 Thread Andreas K. Huettel 

# Andreas K. Huettel  (24 Oct 2014)
# Fails tests (bug 277407), no reverse deps in tree, no releases
# since many years, unlikely to work with uptodate subversion
# Masked for removal in 30 days
dev-perl/SVN-Mirror


-- 

Andreas K. Huettel
Gentoo Linux developer 
dilfri...@gentoo.org
http://www.akhuettel.de/



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[gentoo-dev] last rites: dev-perl/DateTime-Format-DateManip

2014-10-24 Thread Andreas K. Huettel 
# Andreas K. Huettel  (24 Oct 2014)
# Fails tests (bug 421797), no reverse deps in tree, VERY dead
# upstream, last release 10 years ago. Masked for removal in 30 days.
dev-perl/DateTime-Format-DateManip


-- 

Andreas K. Huettel
Gentoo Linux developer 
dilfri...@gentoo.org
http://www.akhuettel.de/



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