Re: volatile access optimization (C++ / x86_64)

2014-12-30 Thread Torvald Riegel
On Fri, 2014-12-26 at 23:19 +, Andrew Haley wrote: > On 26/12/14 22:49, Matt Godbolt wrote: > > At the moment I think the best I can do is to use an inline assembly > > version of the increment which prevents GCC from doing any > > optimisation upon it. That seems rather ugly though, and if any

Re: volatile access optimization (C++ / x86_64)

2014-12-30 Thread Torvald Riegel
On Fri, 2014-12-26 at 22:26 +, Andrew Haley wrote: > On 26/12/14 20:32, Matt Godbolt wrote: > > > I'm investigating ways to have single-threaded writers write to memory > > areas which are then (very infrequently) read from another thread for > > monitoring purposes. Things like "number of uni

Re: 404 @ https://gcc.gnu.org/gcc-5/

2014-12-30 Thread Olaf van der Spek
On 29-12-2014 18:36, Jonathan Wakely wrote: On 29 December 2014 at 15:34, Ed Smith-Rowland wrote: The note on C++14 conformance referred to is not the place for this but: is our C++11 support really less tested and more experimental than our C++03 support at this point? One thing I can think of

Re: 404 @ https://gcc.gnu.org/gcc-5/

2014-12-30 Thread Olaf van der Spek
On 29-12-2014 16:34, Ed Smith-Rowland wrote: The note about C++14 conformance is great as it stands modulo link errors. Why is it great to not mention the experimental qualifier? Do all files / libraries have to be compiled with the same -std option? If so, this option causes ABI issues by its

Re: 404 @ https://gcc.gnu.org/gcc-5/

2014-12-30 Thread Ed Smith-Rowland
On 12/30/2014 07:50 AM, Olaf van der Spek wrote: On 29-12-2014 16:34, Ed Smith-Rowland wrote: The note about C++14 conformance is great as it stands modulo link errors. Why is it great to not mention the experimental qualifier? Do all files / libraries have to be compiled with the same -std o

Re: 404 @ https://gcc.gnu.org/gcc-5/

2014-12-30 Thread Jonathan Wakely
On 30 December 2014 at 15:29, Ed Smith-Rowland wrote: > On 12/30/2014 07:50 AM, Olaf van der Spek wrote: >> >> On 29-12-2014 16:34, Ed Smith-Rowland wrote: >>> >>> The note about C++14 conformance is great as it stands modulo link >>> errors. >> >> >> Why is it great to not mention the experimental

Re: volatile access optimization (C++ / x86_64)

2014-12-30 Thread Matt Godbolt
On Tue, Dec 30, 2014 at 5:05 AM, Torvald Riegel wrote: > I agree with Andrew. My understanding of volatile is that the generated > code must do exactly what the abstract machine would do. That makes sense. I suppose I don't understand what the difference is in terms of an abstract machine of "lo

Re: volatile access optimization (C++ / x86_64)

2014-12-30 Thread Paul_Koning
> On Dec 30, 2014, at 1:32 PM, Matt Godbolt wrote: > > On Tue, Dec 30, 2014 at 5:05 AM, Torvald Riegel wrote: >> I agree with Andrew. My understanding of volatile is that the generated >> code must do exactly what the abstract machine would do. > > That makes sense. I suppose I don't understa

Re: How to upgrade a tool-chain tree...

2014-12-30 Thread Richard Pennington
On 12/28/2014 02:27 PM, Alan Lehotsky wrote: I have a tool chain for an experimental processor, built starting with release or snapshot distributions of binutils-2.21 cgen-20110901 gcc-4.6.1 newlib-1.19.0 gdb 7.2 I'm using SVN for version control locally

Typo ?

2014-12-30 Thread Francois-Xavier Le Bail
Hello, in 'https://gcc.gnu.org/gcc-4.9/changes.html' there is a reference to '-Wzerotrips' Is this not '-Wzerotrip' without 's' ? Cheers, Francois-Xavier