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[filesystem] Junction support on Windows?
by Peter Dimov 02 Jan '15

02 Jan '15

Filesystem provides support for hard and symbolic links, but on Windows, hard links do not work on directories and symbolic links do not work for the majority of users because they require elevation by default. That is why, for example, "b2 headers" was changed to also use junctions, if possible. But if I, for another example, want to replicate "b2 headers" from a C++ program using Filesystem, I can't, because it offers no junction support. Should create_directory_symlink be enhanced to create a junction, if CreateSymbolicLink is not available or fails with ERROR_ACCESS_DENIED?

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[filesystem] resize_file_api leaks a HANDLE
by Peter Dimov 02 Jan '15

02 Jan '15

... when SetFilePointerEx or SetEndOfFile fails. BOOL resize_file_api(const wchar_t* p, boost::uintmax_t size) { HANDLE handle = CreateFileW(p, GENERIC_WRITE, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0); LARGE_INTEGER sz; sz.QuadPart = size; return handle != INVALID_HANDLE_VALUE && ::SetFilePointerEx(handle, sz, 0, FILE_BEGIN) && ::SetEndOfFile(handle) && ::CloseHandle(handle); }

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updated Boost.Test devel->master: documentation needs
by Dave Gomboc 02 Jan '15

02 Jan '15

> What left in docs: > > * general reformating of existing pages and separation to "user's guide" and "advanced usage scenarios" (I am working on this) > * BOOST_TEST tool, including figuring out what to do with old testing tools description and reference > * data driven test cases (Raffi works on this) > * decorators support (Andrzej volunteered to help with this) > * run by name/label description. Including multitude of new syntax options > * figure out doxigen issues > * figure out new format for examples > * few minor issues with Boost.Logos > * investigate Boost.pp style left side menu (optional) > * interaction testing (optional) > * production use of Boost.Test (optional) > * anything else missing from above (hopefully nothing big) > > Any takers? > Gennadiy Thanks for posting this list, Gennadiy. I'll volunteer to write up a section on the production use of Boost.Test. I will, however, need source material in order to do so. Boosters, have you ever or do you now use either Boost.Test or an alternative testing framework in a production-like manner? - with more complicated or less common build systems - when regression testing across multiple versions of dependent libraries - when regression testing across multiple toolchains and/or platforms - as part of deployments within virtualized containers - et cetera If so, could you please describe your setup, either here on-list or privately to myself? I will collect the responses received, and from them, prepare documentation so that people new to Boost.Test can get started with setting up production-quality regression testing environments. Dave

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[compute] Review
by Yiannis Papadopoulos 01 Jan '15

01 Jan '15

Hi, This is my review of Boost.Compute: 1. What is your evaluation of the design? It seems logical to me. It is effectively a wrapper around OpenCL that provides implementations of higher-level algorithms, and allows interoperability with OpenCL and OpenGL. The Boost.Compute name is a bit misleading, as Boost.Compute supports only OpenCL-enabled devices. 2. What is your evaluation of the implementation? There is some code duplication (e.g. type traits) and various other bits and pieces that can be moved to existing Boost components. I think there should be some effort spent towards that. It seems that performance is on par with Thrust. However, there are other libraries out there (e.g Bolt) and multiple devices, so there has to be a more extensive experimental evaluation to say decidedly that it is a good implementation. 3. What is your evaluation of the documentation? Overall, it is pretty good. Given the complexity of the accelerator programming model, a few more elaborate examples in the tutorial would be welcome. 4. What is your evaluation of the potential usefulness of the library? This is difficult to answer. A lot of work has been put in this library and it seems the way to go. The interfaces are clean, the code looks solid and the developer willing. However, there is limited vendor support, there are not enough benchmarks and there are other alternatives that they have both. Given that Boost.Compute is targeted to users that know a thing or two about performance, I don't know how they can be convinced to consider using Boost.Compute against Bolt or Thrust. 5. Did you try to use the library? With what compiler? Did you have any problems? I did using an AMD 7850 on Linux with gcc 4.8. The few examples I tried, compiled and ran fine. 6. How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? I went over the documentation, I glanced over the code and ran a few examples. 7. Are you knowledgeable about the problem domain? I'm in the HPC field. I have extensive experience with MPI, OpenMP, pthreads, and less with TBB, CUDA and OpenCL. 8. Do you think the library should be accepted as a Boost library? This will be a maybe. It is a well-written library with a few minor issues that can be resolved. However, why would someone use Boost.Compute against what is out there? Average users can resort to Bolt or Thrust. Power users will probably always try to hand-tune their OpenCL or CUDA algorithm. How can we test it and prove its performance? Regards, Yiannis

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[compute] Review results
by Antony Polukhin 01 Jan '15

01 Jan '15

Hi all, Extended review period for Boost.Compute library has ended. Here are the review votes for inclusion (+ means include, - means do not include, +/- means conditional include or "probably include, not quite sure"): + Denis Demidov + Sebastian Schaetz + Pavan Yalamanchili - Gruenke,Matt (+ if more backends will be supported) + Asbjørn (mini-review/comments from a library user) + Thomas M (a lot of suggestions) + Paul A. Bristow + Belcourt, Kenneth + John Bytheway +/- Yiannis Papadopoulos (there's already Bolt/Thrust for beginner and pure OpenCL for pros) +/- Vicente J. Botet Escriba (better docs and more performance tests) +/- Jason Newton (there was no explicit answer to the question "shuld be this library accepted into Boost?" but the review was positive in general) To sum up: Compute library becomes part of the Boost. Great thanks to all for the reviews and comments! Huge work was done and the issues raised are essential for library success. P.S.: Happy new year everyone! P.P.S.: Hope I did not miss some review! In case of any error, please let me know! -- Best regards, Antony Polukhin

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[compute] review
by Vicente J. Botet Escriba 01 Jan '15

01 Jan '15

Hi, I have no time to do a complete review. Anyway here it is my minimal review *1. What is your evaluation of the design?** *** I would prefer that the algorithms take as first parameter the queue (which could be abstracted to an asynchronous executor). The performances let think that there is no interest in using the library for containers having less than 10^4/10^5 elements. Even if this is considered a low level library, the documentation should show how a library writer could make use of the provided interface to provide a higher one. I would prefer that the library make use of std::future or boost::future class instead of adding an additional one. Do the author tried to make use of the existing futures? if yes, which problems were found? I'm missing a range interface to most of the algorithms. I suspect that as this is a C++03 library it doesn't take advantages of some interesting C++11+/C++14 features. It is not clear which operations are synchronous, which ones could block, ... In order to get the native OpenCl handle I suggest to name the function get_native_handle instead of get. *2. What is your evaluation of the implementation?* I've not see at the implementation. *3. What is your evaluation of the documentation?* The documentation lacks of some core tutorials. I was unable to have an idea of what a context is, what can be done with a command_queue, what is a Kernel, a pipe, ...? Does it mean that the user must know OpenCL? The reference documentation should follow he C++ standard way, including pre-conditions, effects, synchronization, throws clauses. I would appreciate a description of the algorithms used, how the parallelism is used? is this completely managed by OpenCL or do the library something else? *4. What is your evaluation of the potential usefulness of the library?** *** This is essentially an optimization library. It should be quite useful, but the performances results don't probe it. *5. Did you try to use the library? With what compiler? Did you have any problems?** * No.* *** *6. How much effort did you put into your evaluation? A glance? A quick reading? In-depth study?** *** A glance. *7. Are you knowledgeable about the problem domain?* Yes and not. I don't know about OpenCL, but I'm aware of the current parallel proposals. *8. Do you think the library should be accepted as a Boost library? ** * As I have not taken too much time I'm unable to say that this library should not be included in Boost. So I vote to include it conditionally, subject to: * I would need some performances that probe the library is better than using standard STL containers in most of the cases. * The documentation should be completed with more tutorials and a better reference documentation. Best, Vicente

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[compute] review
by Gruenke,Matt 31 Dec '14

31 Dec '14

> 1. What is your evaluation of the design? I agree with other comments made about synchronization. The design should be more explicit about what's asynchronous, and ideally utilize only one mechanism for synchronization. One approach that would have made this clearer is if high-level operations were actually objects that got posted to the command_queue. Regarding synchronization, I'm a also bit concerned about the performance impact of synchronizing on all copies to host memory. Overuse of synchronization can easily result in performance deterioration. On this point, I think it might be worth limiting host memory usable with algorithms, to containers that perform implicit synchronization to actual use (or destruction) of results. Give users the choice between that or performing explicit copies to raw types. Also, I agree with Thomas M that it'd be useful for operations to return events. That said, if you told me it doubled the overhead involved in dispatching operations, I'd suggest to make it optional through overloads or via a mechanism in the command_queue itself. > 2. What is your evaluation of the implementation? It seems a bit heavy to be header-only. I'd agree with Andrey Semashev, regarding thread safety, except I think it shouldn't be an option at all. That said, not all operations on all objects need be thread safe. I think the Boost.ASIO documentation provides a good example of how to express different thread safety limitations. Now, I haven't examined the use of thread-local storage, but do you feel there's a strong case to be made for the thread safety it's providing (especially, given that you seem to feel it's non-essential)? I'm a bit concerned about the use of type names ending in '_', such as float4_. Is this consistent with Boost conventions? I've only seen that used in other Boost libraries to denote class member variables. I didn't notice any unit tests specifically intended to verify exception-safety. I'd want to know that had been thoroughly vetted, before I'd consider using Boost.Compute in production code. Finally, based on the docs, it seems there's a bug in boost::compute::command_queue::enqueue_copy_image_to_buffer() and boost::compute::command_queue::enqueue_copy_buffer_to_image(). The region and origin parameters should be arrays, in the 2D and 3D cases. If this discrepancy is intentional, it should be noted. I haven't exhaustively reviewed the reference docs, so there might be other issues of this sort. > 3. What is your evaluation of the documentation? It needs more and better-documented tutorials (and I'm including the "Advanced Topics", here). Some of the reference pages could use more details, as well, especially concerning synchronization and exception usage. Regarding exceptions, there should be discussion of specifically what is invalidated by which kinds of errors. If any errors are non-recoverable, this should also be called out and perhaps derived from a different or additional baseclass (not a bad use case for multiple inheritance, actually). I agree with Mathias Gaunard that it would be helpful to discuss computational complexity, device memory requirements, and the various methods used to implement some of the algorithms. You could continue to omit these details on the simple algorithms, though. > 4. What is your evaluation of the potential usefulness of the library? This is my biggest misgiving, by far. In the very near future, I expect developers will opt for either SYCL (https://www.khronos.org/opencl/sycl) or Bolt (https://github.com/HSA-Libraries/Bolt) SYCL provides a modern, standard C++11 wrapper around OpenCL, with better concurrency control and support for integrating kernels inline. Bolt provides many of the same higher-level abstractions found in Boost.Compute, but with forthcoming support for HSA. To have the kind of lasting relevance and broad applicability to which all Boost libraries should aspire, I think Boost.Compute should be architected to support multiple backends. Though OpenCL support is currently ascendant, it's far from universal and is already flagging on some platforms (Nvidia, not the least). And HSA provides a foundation on which alternatives are actively being built. Most importantly, there exist multitudes of multi-core and multiprocessor systems which lack OpenCL support. It would be eminently useful to support these with such backends as thread pool, OpenMP, etc. And backends could be added to support new technologies, as they mature. > 5. Did you try to use the library? With what compiler? Did you have any problems? I downloaded and inspected the sources and some examples. I didn't have any questions or concerns that would be addressed by experimentation. > 6. How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? Review of the documentation, some sources, some examples, and a refresher on SYCL & Bolt. I also read all of the reviews and replies sent thus far. > 7. Are you knowledgeable about the problem domain? I've been developing production code for parallel and heterogeneous computing platforms for the majority of the last 16 years. I've followed OpenCL since version 1.0 was finalized. I've also submitted bug reports and minor patches for Khronos' official C++ OpenCL interface. > 8. Do you think the library should be accepted as a Boost library? Be sure to say this explicitly so that your other comments don't obscure your overall opinion. Not in its current state. The primary issue is that it's too OpenCL-centric. It should support more backends, even if these are just compile-time options. This is crucial for both current and lasting relevance. Beyond that, better concurrency control is crucial for optimum performance. If done well, it could even help further reduce usage errors. Matt ________________________________ This e-mail contains privileged and confidential information intended for the use of the addressees named above. If you are not the intended recipient of this e-mail, you are hereby notified that you must not disseminate, copy or take any action in respect of any information contained in it. If you have received this e-mail in error, please notify the sender immediately by e-mail and immediately destroy this e-mail and its attachments.

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Boost.Build files at superproject root
by Peter Dimov 31 Dec '14

31 Dec '14

Currently, the Boost root contains the following files: boost-build.jam boostcpp.jam boostcpp.py bootstrap.bat bootstrap.sh Jamroot which are part of Boost.Build and so their rightful place is in the submodule. Would it be possible to move them there, and leave only minimal forwarding shims (that would never need to change) in the superproject?

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[compute] Review
by John Bytheway 31 Dec '14

31 Dec '14

Here's my review. 1. What is your evaluation of the design? The design of building on OpenCL seems sound, for the reasons Kyle has explained. The fact that it has real users is very encouraging. I don't really like the name (I was unable to guess what the library was about from the name), but it's not worth changing at this point. I am worried about the compile-time configuration with macros. I would hope that BOOST_COMPUTE_HAVE_THREAD_LOCAL could be read from Boost.Config. For the two features which require linking against other Boost libraries, my instinct would be to have them on by default, rather than off by default (that should be easier if and when Boost.Compute is part of the Boost distribution). It would be very nice to have range versions of all the algorithms. I find myself using the boost::range algorithms much more than the std:: ones these days. Similarly, it would be good to provide the safer 4-iterator versions of equal, is_permutation, mismatch (and any I've forgotten) as were added to C++14. Some minor things: - Consider renaming boost::compute::lambda to be consistent with one of the other placeholder-containing namespaces from std or Boost. (You can keep the old name as an alias for backwards-compatibility). - Why the default of .25 as the bernoulli_distribution parameter? - Did you consider using Boost.Predef for your version macro? 2. What is your evaluation of the implementation? Only looked at a couple of things while trying to understand the docs. 3. What is your evaluation of the documentation? Overall, not too bad. More tutorial would be good. In particular, something using some of the standard algorithms. Some concerns: - All the header links off <http://kylelutz.github.io/compute/boost_compute/reference.html> are broken. - All or most of the things in "See also" sections look like they ought to be links but aren't. - For all your function parameter documentation, the list of parameters seems to be sorted alphabetically by parameter name rather than in the order they are passed to the function. This is really weird... - As others have mentioned, some kind of complexity estimate or promise for the algorithms is very important. In particular it would be good to understand how much parallelism they take advantage of and how they ought to scale with device compute capability. - The warning about accumulate being slow for floats should be much more prominent. - <http://kylelutz.github.io/compute/boost/compute/copy.html> mentions copying from e.g. a std::list to a compute::vector. It would be nice if it gave some kind of indication as to how efficient we can expect such an operation to be. In particular, I guess it ought to do some kind of buffering on the host? - The way I normally copy into vectors is call v.reserve(...) and then copy to std::back_inserter(v). I tried that with a compute::vector and unsurprisingly it was very inefficient. I see you already warned about this in the push_back docs, but perhaps it should also be highlighted in the documentation of compute::copy. - Is there no version of inclusive/exclusive_scan or iota using an arbitrary associative operator? - <http://kylelutz.github.io/compute/boost/compute/includes.html> it's unclear whether the subrange has to be contiguous. - min_element and max_element should cross-reference minmax_element. - What source of randomness does random_shuffle use? - Why does reduce return its result through an OutputIterator? - <http://kylelutz.github.io/compute/boost/compute/remove.html> Does this really remove things or use std::remove semantics? You should clarify and document the return value. (Same with remove_if, unique) - I can see how sort_by_key might be useful, and I'm slightly surprised that there's no stable_sort_by_key (which seems like it would be more useful than stable_sort). Any particular reason? - The boost/compute/types headers docs seem to be broken or missing. In particular I couldn't find reference documentation for float4_ et al. - I was interested to see allocators, but the docs seem uninformative: <http://kylelutz.github.io/compute/boost/compute/pinned_allocator.html> - Given the confusion with std::future, you might want to clarify whether compute::future's destructor blocks. - Also, <http://kylelutz.github.io/compute/BOOST_COMPUTE_CLOSURE.html> doesn't explain what format the lists (arguments and capture) should be in. Preprocessor functions often take lists in other formats, such as a Boost.PP Sequence <http://www.boost.org/doc/libs/1_57_0/libs/preprocessor/doc/data/sequences.h…>, and your example only has one-element lists, so it's not enough to clarify this point. (To be clear: I'm not suggesting you should use Boost.PP sequences, merely that you should make it clear in the docs whether you are). - <http://kylelutz.github.io/compute/BOOST_COMPUTE_CL_CALLBACK.html> is empty, as is <http://kylelutz.github.io/compute/BOOST_COMPUTE_MAX_ARITY.html> - <http://kylelutz.github.io/compute/boost/compute/valarray.html> - presumably compute::valarray has overloaded arithmetic operators? Are they mentioned anywhere? - <http://kylelutz.github.io/compute/boost/compute/vector.html> the unusual behaviour of vector's size_t constructor (not initializing the elements) should be warned more prominently. - <http://kylelutz.github.io/compute/boost/compute/device.html> the documentation of the enum type in the synopsis seems to be messed up. Similarly memory_object. - <http://kylelutz.github.io/compute/boost/compute/function.html> I'm puzzled by this interface. What's the name for? Would one ever use this constructor rather than e.g. make_function_from_source? - <http://kylelutz.github.io/compute/boost/compute/field.html> My reading of this is that when you get the type wrong you are guaranteed some kind of meaningful error report, and not just undefined behaviour; is that right? Perhaps you should clarify. - I can't guess what atomic_min and atomic_max do. - The right arrow ('next') link from <http://kylelutz.github.io/compute/boost/compute/atomic_xor.html> is broken (looks like the docs for the placeholders don't work). - The iterators should state what iterator category they have. - I can't guess what svm_ptr is for. Later I discovered svm_alloc and svm_free. Is there an RAII way to manage these things? - What does default_device do if there are no devices? Do the various environment variables mentioned have any kind of precedence? (Probably linking to the corresponding OpenCL docs is sufficient for such questions). Do they have to be exact matches? Are they case-sensitive? - What does find_device do if the requested device does not exist? - Can you give examples for type_definition? My guess was that it did the thing which type_name later turned out to do... - BOOST_COMPUTE_ADAPT_STRUCT should state that it must be used at global scope (i.e. not within a function or other namespace). - Congratulations for getting compile-time detection of internal padding into BOOST_COMPUTE_ADAPT_STRUCT :). You might want to mention in the docs that this will be detected, so people don't worry too much. - It looks like the performance tests don't include the time for copying data to (and, where applicable, from) the device. You should mention this on the Performance page. - You should probably add C++AMP to your things compared with in the FAQ. 4. What is your evaluation of the potential usefulness of the library? High. I've wanted something like this in the past and not found this. 5. Did you try to use the library? With what compiler? Did you have any problems? I used it with g++ 4.8.2 in C++1y mode. Some quick tests seemed to work OK, and indeed I was able to sort some large vectors of scalars faster using boost::compute::sort than std::sort, which is nice. I was pleased to see that 64-bit integers were handled fine. 6. How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? Couple of hours reading and trying simple examples. 7. Are you knowledgeable about the problem domain? I have done a couple of small projects with CUDA, and am generally knowledgeable, but with no previous OpenCL experience. 8. Do you think the library should be accepted as a Boost library? Be sure to say this explicitly so that your other comments don't obscure your overall opinion. Yes. OpenCL seems to have fairly broad acceptance, but is rather difficult to use safely and with C++-isms. This library fills a useful niche. In an ideal world it will eventually be rendered obsolete by things like parallelism entering the standard library, but I doubt that will happen soon if at all. This provides a good solution now, and we shouldn't dismiss it simply because something sparkly is approaching, which may or may not turn out to be awesome and widely adopted. This library has clearly been a lot of work. Congratulations on making it this far, I hope the review is not too stressful :). John Bytheway

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[system] Problem with boost::system::system_category() under QNX Momentics
by Piotr Orzechowski 31 Dec '14

31 Dec '14

At the beginning I must assure You that I've tried almost every solution from similar topics , still they didn't solve my issue. I'm building binaries from Boost 1.57 using **MinGW**. Boost libraries I'm using: *thread* and *system* build without any errors. I was trying: > toolset=gcc --target-os=qnxnto and toolset=gcc --target-os=qnx, both didn't work. I'm including correctly both libraries: > -lboost_system-mgw48-mt-d-1_57 -lboost_thread-mgw48-mt-d-1_57 after using: > `#define BOOST_SYSTEM_NO_DEPRECATED` I got rid of `boost::system::generic_category()` error, still I can't get rid of: > boost::system::system_category() I'm working in **QNX Momentics**. I'm totally out of ideas, I'm really looking forward for any help I can get.

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Define to test for deprecated std::auto_ptr
by Fletcher, John P 31 Dec '14

31 Dec '14

I have some tests which are throwing up std::auto_ptr as deprecated with C++11. Is there a define that can be tested for in user code so that I can switch to std::unique_ptr when it is available? Something like this: #ifdef BOOST_NO_CXX11_UNIQUEPTR // use auto_ptr #else // use unique_ptr #endif Is there a general flag for C++11 or C++14 or is it all done on particular features? Thanks John

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[compute] CL_QUEUE_OUT_OF_ORDER_EXEC_MODE_ENABLE
by Gruenke,Matt 31 Dec '14

31 Dec '14

I assumed there was some behind-the-scenes mechanism to maintain order of higher level operations, but I hadn't dug around to find them. I thought maybe there was an event object embedded in the device memory containers, used to track any pending writes to them, that could be added to the wait list of subsequent operations. But I don't see anything like this. So, will enabling out-of-order execution will break the higher level operations? Or am I missing something? Matt ________________________________ This e-mail contains privileged and confidential information intended for the use of the addressees named above. If you are not the intended recipient of this e-mail, you are hereby notified that you must not disseminate, copy or take any action in respect of any information contained in it. If you have received this e-mail in error, please notify the sender immediately by e-mail and immediately destroy this e-mail and its attachments.

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[compute] Review period starts today December 15, 2014, ends on December 24, 2014
by Antony Polukhin 31 Dec '14

31 Dec '14

Dear All, Review of the Compute library starts today on Mon 25st of December 2014 and will last for ten days. The Compute library provides a C++ interface to multi-core GPGPU and CPU computing platforms based on OpenCL. The project is hosted on GitHub at https://github.com/kylelutz/compute. Docs are available at http://kylelutz.github.io/compute/ Sources could be downloaded as a ZIP archive via https://github.com/kylelutz/compute/archive/master.zip Some pre-official reviews could be found in Boost Library Incubator: http://rrsd.com/blincubator.com/reviews/?library_id=669 Please, answer the following questions in your review: 1. What is your evaluation of the design? 2. What is your evaluation of the implementation? 3. What is your evaluation of the documentation? 4. What is your evaluation of the potential usefulness of the library? 5. Did you try to use the library? With what compiler? Did you have any problems? 6. How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? 7. Are you knowledgeable about the problem domain? And finally, every review should answer this question: 8. Do you think the library should be accepted as a Boost library? Be sure to say this explicitly so that your other comments don't obscure your overall opinion. -- Best regards, Antony Polukhin

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[compute] Review comments
by Asbjørn 30 Dec '14

30 Dec '14

Hi, not a proper review, just some comments from a library user based on studying documentation and writing a couple of simple programs using Boost.Compute on Intel's and NVIDIA's OpenCL implementations (i7 CPU and GTX970 GPU respectively). I used MSVC2013 for the tests. Some of these comments I've shared previously on this list, but I'm repeating them here for completeness. I have some background in heterogeneous development and OpenCL in particular, but I'm no expert. I found Boost.Compute easy to pick up and providing a nice C++ layer, with a nice mix of low and high level. Comments in no particular order: 1) As a library user and one who's not a C++ guru by any means, the error messages thrown up when passing incorrect parameters can be quite confusing. For example, first time I tried to use Boost.Compute I managed to not pass the ouput iterator parameter to transform(), so that the lambda expression ended up in that position instead. This resulted in several very confusing errors inside result_of.hpp, with no errors anywhere near my or Boost.Compute source code. It would be nice if the compilation could fail in more informative manners. 2) I did miss async versions of the algorithms, so it's possible to chain together multiple calls. Even though all the data sits on the compute device, the overhead of waiting for each operation to finish before queuing the next can make the compute gains completely irrelevant. 3) I think relevant calls should have a non-throwing form returning an error code, ala Boost.ASIO. 4) Threading has been mentioned in this list. At the very least the documentation should be updated to clearly state the thread safety of each call/class, ala Boost.ASIO. Beyond that I would like to be able to share a context between several threads, each which could contain their own queue and device. 5) If thread safety or similar important features requires a compiled part, I wouldn't mind Boost.Compute being non-header-only. Though if possible making it optional like other Boost libraries do would be great. 6) The tests, and preferably the performance tests as well, should have some way of testing all devices across all platforms. Currently they only test the default device on the default platform it seems. This is insufficient IMHO. 7) I'd like some way of defining user functions either as lambda expressions, raw OpenCL-C code via make_function_from_source or both, which can be used in lambda expressions for say transform(). Something like function<int (int)> sqr = _1 * _1; transform(inp.begin(), inp.end(), out.begin(), sqr(2 * _1 + 1)), queue); Overall I think Boost.Compute can be useful right now for some use-cases, and it has good potential to be significantly more useful with a bit more work. Just my 2 øre. Cheers - Asbjørn

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[filesystem] imbue_utf8
by Peter Dimov 30 Dec '14

30 Dec '14

Since nowadays it's very common for programs to use UTF-8 for path encoding everywhere, I suggest that in addition to path::imbue( loc ), there should be path::imbue_utf8(), which imbues a UTF-8 codecvt facet. Since this is the default on Mac OS X, the implementation is already present, but the user has no way to get to it.

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[config] Macro for detecting thread_local storage support
by Kyle Lutz 30 Dec '14

30 Dec '14

I have looked but been unable to find any macro in Boost.Config for detecting compiler support for the C++11 thread_local storage specifier. Does such functionality exist? I would like to use something like this to automatically detect compiler support for thread_local for use by the proposed Boost.Compute library. Currently I rely on the users defining BOOST_COMPUTE_HAVE_THREAD_LOCAL in order to enable support. Hopefully there is a better way? -kyle

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Re: [boost] [test] boost.test owner unresponsive to persistent problems for multiple years
by Dave Gomboc 30 Dec '14

30 Dec '14

I get the digests, so I'm quoting from a number of different emails on this thread in this message. > > Both contain a fix for this. On stack overflow the proposed fix is > > literally a single line change. > > The issue is addressed in devel branch with somewhat better fix > long long time ago. It is important that tickets be updated to reflect such information. > > If there are issues fixed in develop branch, it would help a lot > > to inform users by updating the tickets accordingly. > > Here is a blanket update message: at this point all the issues with > Boost.Test are fixed on devel branch ;). This doesn't help people who filed a ticket (perhaps years ago) but don't happen to catch this email. > > This has been a problem for about 5 years and these simple fixes don't > > make it into the library. > > This is going to be released as part of the effort of merging devel into > master. Now, when this happens depends only on docs upgrade. It seems that in addition to documentation upgrades/improvements there is at least also the issue of identifying all Boost.Test-related tickets that are currently outstanding, verifying that the issue raised within them is indeed resolved within the development branch (rather than just assuming this is true), and updating the ticket to reflect that the problem has been resolved in the development branch (though it should not be closed yet until a new Boost release comes out with the fix in place). > All in all "devel to master upgrade" is one target I really want to reach > and is what I plan to concentrate my effort on. You are still welcome to > help with this if you are up to it. Excellent! If it has really been five years (or even if it has been only one full year) since this last happened, then may I suggest that this should be your sole target for Boost.Test until this task is accomplished, that your target should be prior to the next major release of Boost, and that obtaining assistance be an important part of your plan to accomplishing this task within this timeframe? To that end, could you please provide for the Boost community a detailed outline of exactly what remains to be done in order for the merge of the latest Boost.Test to master to be completed? Please be clear about exactly what others can help with, and in the cases where you think nobody else can help you, why that is so. Please do so here on the mailing list rather than ask people to contact you privately about it, so that more people will know what remains to be done and may be willing to lend a hand so it can get done. > > 1. What are the reason(s) why-list_content is not (yet) > > added to the release? Is there any schedule for its release? > > I need to document all these new features to release new Boost.Test Can you provide a list of these new features alphabetically by name with a one-sentence description? Boosters can sign up for writing documentation paragraphs, can contribute them here, and you can collect and use them. > > Yes. I fully agree with this statement. I hope to get back to this list > > with more concrete schedule soon. And if you are interested to push this > > even sooner - please feel free to help. > > That's great news. I know a vast amount of work has gone into develop > and we'll all benefit when it finally gets merged into master. Yes, I'm > happy to support this effort as best I can. Feel free to contact me > off-list. Rather than contact people off-list, I urge you to get all of the outstanding work into the open and use this mailing list for co-ordination not only so that people can contribute without overlapping their effort needlessly, but so that the current status is visible to all of us. That last point is rather important: I know of projects that have chosen alternative testing frameworks simply because of the lack of visibility re: Boost.Test. > Thanks for working hard to move this forward. Boost.Test has always been > a critical library and as a result somewhat of a thankless task to > maintain given the constant risk of breakage across Boost as a whole. > Thanks for persevering. I absolutely concur with this. Your efforts are appreciated, Gennady! You've been shouldering the entire burden for too long. I think that by publicly coordinating and leading the remaining effort to get the latest Boost.Test onto master, you'll be able to achieve this goal more quickly. Dave

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[filesystem] Request for help with unresolved tickets
by Beman Dawes 29 Dec '14

29 Dec '14

Boost.Filesystem has roughly 140 unresolved tickets, and far too many are more that a year old. Some are up to four years old. That's horrible, and entirely my fault. I really dislike processing most bug reports, so leave them until I have nothing else to do, which is roughly never. But a few bug reports are actually fun to process. These are the ones that provide a little test program that unambiguously illustrates the problem and includes full information about the compiler, platform, version of boost, etc. To encourage more such dream tickets, I've added a little bug reporting framework with docs to filesystem's develop branch. It depends on a new header (boost/detail/lightweight_test_report.hpp) that's been added to the detail library's develop branch. The hope is that this will lead to more test programs that make it easy to reproduce bugs to (1) speed my processing of tickets and (2) ease handing off tickets to other developers for fixes. There are several ways boosters can help: * Review and try out the instructions at http://boostorg.github.io/filesystem/issue_reporting.html. (Don't expect all links to work.) Were you able to easily follow these instructions? What would you like to see added or removed? * Look through the bugs in https://svn.boost.org/trac/boost/report/53, pick one you think would benefit from a test program, and add a test program as described in http://boostorg.github.io/filesystem/issue_reporting.html. (Do a git pull on develop branch of detail and filesystem libraries first.) Were you able to easily follow these instructions? What would you like to see added or removed? Thanks, --Beman

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[multiprecision] [detail] [number_base.hpp] Ambiguous partial specialization for canonical_imp
by Sergey Sprogis 29 Dec '14

29 Dec '14

It looks like boost/multiprecision/detail/number_base.hpp header in one of the later trunk versions has ambiguous partial specialization problem which Oracle Studio 12.4 C++ compiler detects. It can be also detected by gcc-4.8.2 as small 35 lines independent test case below made from this header shows. gcc -c -std=c++11 t.cc # gcc-4.8.2 compilation t.cc:17:62: error: ambiguous class template instantiation for 'struct canonical_imp<number<cpp_dec_float<50u>, (expression_template_option)1u>, cpp_dec_float<50u>, int_<3> >' CC -c -std=c++11 t.cc # Oracle Studio 12.4 C++ compilation "t.cc", line 17: Error: Ambiguous partial specialization for canonical_imp<Val, Backend, Tag><number<cpp_dec_float<50, int, void>, 1>, cpp_dec_float<50, int, void>, int_<3>>, canonical_imp<Val, Backend, int_<3>> and canonical_imp<number<B, 1>, Backend, Tag>. t.cc ================================== template< bool B> struct enable_if_c{ typedef bool type; }; template< int N > struct int_{}; enum expression_template_option {et_on=1}; template <class Backend, expression_template_option ExpressionTemplates> class number; template <class Val, class Backend, class Tag> struct canonical_imp { typedef int type; }; template <class B,class Backend,class Tag> struct canonical_imp<number<B,et_on>,Backend,Tag> { typedef B type; }; template <class Val, class Backend> struct canonical_imp<Val,Backend,int_<3>>{ typedef Val type; }; template <class Val, class Backend> struct canonical { typedef typename canonical_imp<Val, Backend, int_<3>>::type type; }; template<typename From, typename To> struct is_restricted_conversion { typedef bool type; }; template <class Backend, expression_template_option ExpressionTemplates> class number { public: number() {} template <class V> number(const V& v,typename enable_if_c<!is_restricted_conversion<typename canonical<V,Backend>::type,Backend>::value>::type * =0){} }; template <unsigned Digits10, class ExponentType = int, class Allocator = void> class cpp_dec_float; template <unsigned Digits10, class ExponentType, class Allocator> class cpp_dec_float { public: cpp_dec_float() {} }; template <class RealType> void instantiate(RealType) {} typedef number<cpp_dec_float<50>, et_on> test_type; void foo() { instantiate(test_type()); } =============================== Any suggestions how to fix this? Thanks, Sergey

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[githelp] Pulling to arbitrary branch?
by Rene Rivera 29 Dec '14

29 Dec '14

I have a pull request against one branch (master). But I want to pull it into a different branch (develop). Is that possible? And if so, how? -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

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[filesystem] ISO TS 18822, Technical Specification - File System
by Beman Dawes 29 Dec '14

29 Dec '14

The filesystem TS has been unanimously approved by ISO. 32 countries voted. The document has been forwarded to the ISO Central Secretariat for publication. The current working draft, which is technically the same as the TS but may have editorial corrections, is available at http://cplusplus.github.io/filesystem-ts/working-draft.html Many thanks to all the Boost folks who contributed so much to the Boost library that became the ISO TS! The C++ standards committee Filesystem Study Group will continue to operate, and will issue further TSes as further proposals dictate, and will continue to publish a working paper as issues for the TS are corrected. Happy Boost New Year, --Beman

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What does "install dist-lib" in the inspect Jamfile do?
by Peter Dimov 29 Dec '14

29 Dec '14

I'm looking at Boost.Inspect's Jamfile as an example of how installation is done, and it has: install dist-bin : inspect : <install-type>EXE <location>../../../dist/bin : release ; install dist-lib : inspect : <install-type>LIB <location>../../../dist/lib : release ; The first one I get; it copies inspect.exe to dist/bin. But what does the second one do?

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[core] A better boost::swap
by Antony Polukhin 29 Dec '14

29 Dec '14

Hi all, Ion Gaztañaga implemented a very good swap that used move emulation when possible and has all the features of boost::swap: http://www.boost.org/doc/libs/develop/boost/move/adl_move_swap.hpp I've tried to change default implementation of ::boost::swap to #include <boost/move/adl_move_swap.hpp> namespace boost { template<class T1, class T2> BOOST_GPU_ENABLED void swap(T1& left, T2& right) { ::boost::adl_move_swap(left, right); } } All the tests of the Boost.Swap passed. Ion's solution looks better than existing boost::swap. Are there any reasons not to change the existing implementation of Boost.Swap to Ion's version? -- Best regards, Antony Polukhin

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Dependency Report (was RE: [core] A better boost::swap)
by Fletcher, John P 28 Dec '14

28 Dec '14

________________________________________ >From: Boost [boost-bounces(a)lists.boost.org] on behalf of Peter Dimov [lists(a)pdimov.com] >Sent: 27 December 2014 21:21 >To: boost(a)lists.boost.org >Subject: Re: [boost] [core] A better boost::swap >Andrzej Krzemienski wrote: ... >> http://www.pdimov.com/tmp/report-d5ca5be/module-levels.html >I've generated a new report at >http://www.pdimov.com/tmp/report-b1adfee/module-levels.html That is very interesting and helpful. Is there a location where it can be referenced? Thanks John

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Interactive metaprogramming shells
by Abel Sinkovics 28 Dec '14

28 Dec '14

Hi, I've built interactive shells for preprocessor and template metaprogramming. I've been using them for development and debugging of metaprograms and I think Boost developers could also find them useful. You can type in (metaprogramming) expressions which get evaluated and the result is displayed immediately. For example you can type boost::mpl::push_front<boost::mpl::vector<int, char>, double>::type and you get boost_::mpl::vector<double, int, char> as the result (the boost_ namespace is used because there are some tricks there to make the output more readable). As an example for the preprocessor shell you can type BOOST_PP_REPEAT(3, foo BOOST_PP_TUPLE_EAT(3), ~) and you get foo foo foo as the result. The tools are based on the Boost.Wave library and Clang. You can get them here: Preshell for preprocessor: https://github.com/sabel83/preshell Metashell for template metaprograms: https://github.com/sabel83/metashell You can also try them from your browser here: http://abel.web.elte.hu/shell Feedback is welcome. Regards, Ábel

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