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explicit-failures-markup.xml
by Niall Douglas 30 Jan '19

30 Jan '19

I'm trying to tell the Boost regression matrix that GCC 8 failures are to be expected using explicit-failures-markup.xml, but it seems to not be working: https://www.boost.org/development/tests/master/developer/outcome.html Here is my explicit-failures-markup.xml: <?xml version="1.0" encoding="utf-8"?> <explicit-failures-markup>  <library name="outcome"> <mark-unusable> <toolset name="clang-linux-3*"/> <toolset name="gcc-3*"/> <toolset name="gcc-4*"/> <toolset name="gcc-5*"/> <toolset name="gcc-mngw-3*"/> <toolset name="gcc-mngw-4*"/> <toolset name="gcc-mngw-5*"/> <toolset name="msvc-7*"/> <toolset name="msvc-8*"/> <toolset name="msvc-9*"/> <toolset name="msvc-10*"/> <toolset name="msvc-11*"/> <toolset name="msvc-12*"/> <toolset name="msvc-13*"/> <toolset name="msvc-14.0.*"/> <note author="Niall Douglas">Complete C++14 support is the minimum requirement.</note> </mark-unusable> <mark-expected-failures> <toolset name="gcc-8*"/> <note author="Niall Douglas">GCC 8 currently ICEs with Outcome's unit tests in C++ 17 or later.</note> </mark-expected-failures> </library> </explicit-failures-markup> What am I doing wrong? Thanks, Niall

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[lexical_cast] Assumed internal double conversion of float?
by Brian Kuhl 30 Jan '19

30 Jan '19

Hi Boost experts, We are chasing down some test failures with floats on VxWorks using the Dinkum clib and c++lib. We are testing with clang on Intel and Arm targets and GCC on PowerPC targets. An example failure at the bottom of this email. We have determined that boost::detail::lcast_get_precision<float>() is returning 9, well in access of the defined FLT_DIG of 6, or the practical float limit of 6.92. Specifically this code here: bool shl_real_type(float val, char* begin) { using namespace std; const double val_as_double = val; finish = start + #if defined(_MSC_VER) && (_MSC_VER >= 1400) && !defined(__SGI_STL_PORT) && !defined(_STLPORT_VERSION) sprintf_s(begin, CharacterBufferSize, #else sprintf(begin, #endif "%.*g", static_cast<int>(boost::detail::lcast_get_precision<float>()), val_as_double); return finish > start; } Where does boost::detail::lcast_get_precision<float>() come from, and why is it 9 ? Is it perhaps assuming some intermediate double conversion internally? In Dinkum's C library, Plager conservatively does not promote to a double, when converting to a string. Many thanks, Brian Wind River ->cmd "LD_LIBRARY_PATH=/opt/TestTriggerLocalPath/Workspace/vx7-boost/2019-01-13/vsb/app/boost/fsl_imx6_llvm_up_32_vxWorks/usr/root/llvm/bin;/opt/TestTriggerLocalPath/Workspace/vx7-boost/2019-01-13/vsb/app/boost/fsl_imx6_llvm_up_32_vxWorks/usr/lib/common" [vxWorks *]# cd /opt/TestTriggerLocalPath/Workspace/vx7-boost/2019-01-13/vsb/app/boost/fsl_imx6_llvm_up_32_vxWorks/3pp/BOOST/boost_1_68_0/status [vxWorks *]# run -x -t 0x01000000 -u 100000 -- ../bin.v2/libs/lexical_cast/test/lexical_cast_float_types_test.test/clang-vxworks/debug/cross-compile-vxworks/static-only-on/lexical_cast_float_types_test.vxe Launching process '../bin.v2/libs/lexical_cast/test/lexical_cast_float_types_test.test/clang-vxworks/debug/cross-compile-vxworks/static-only-on/lexical_cast_float_types_test.vxe' ... Process '../bin.v2/libs/lexical_cast/test/lexical_cast_float_types_test.test/clang-vxworks/debug/cross-compile-vxworks/static-only-on/lexical_cast_float_types_test.vxe' (process Id = 0x20482f10) launched. Running 3 test cases... unknown location(0): [4;31;49mfatal error: in "lexical_cast float types unit test/test_conversion_from_to_double": boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector<boost::bad_lexical_cast> >: bad lexical cast: source type value could not be interpreted as target [0;39;49m ../libs/lexical_cast/test/lexical_cast_float_types_test.cpp(299): [1;36;49mlast checkpoint [0;39;49m unknown location(0): [4;31;49mfatal error: in "lexical_cast float types unit test/test_conversion_from_to_long_double": boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector<boost::bad_lexical_cast> >: bad lexical cast: source type value could not be interpreted as target [0;39;49m ../libs/lexical_cast/test/lexical_cast_float_types_test.cpp(299): [1;36;49mlast checkpoint [0;39;49m

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GSoC 19
by Sandesh Ghanta 30 Jan '19

30 Jan '19

Hey All, I am Sandesh Ghanta, a junior majoring in Computer Science and Engineering. I am interested in contributing to boost and would also like to work with boost in GSoC 19. I am good with C, C++, data structures, algorithms and am currently trying to fix some issues in boost. As I am a beginner to boost I am currently confused as to what project to contribute to, I have been looking at the various issues available to see what I am interested in, but it would be really helpful if someone could guide me. Yours Sincerely, Sandesh Ghanta, FOSS@Amrita <http://amfoss.in> GitHub <https://github.com/sandeshghanta> | Codechef | <http://www.codechef.com/users/sandeshghanta>Codeforces <http://www.codeforces.com/profile/sandeshghanta>

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[gsoc2019] Searching for student
by Damian Vicino 30 Jan '19

30 Jan '19

Hi, I would like to mentor again this year. Some projects I'm particularly interested are getting safefloat or real ready for a formal review (both projects are from previous years and near completion). I'm also open to other projects too. Just ping me with an idea of what you would like to do. Best regards, Damian

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LEAF has been refactored, it now has a much simplified error handling interface
by Emil Dotchevski 29 Jan '19

29 Jan '19

LEAF is a C++11 error handling library for use in low-latency environments. I'm looking for a Boost Review Manager. Any one of you good people willing to volunteer? :) https://zajo.github.io/leaf/ Features: -Header-only, no dependencies. - No dynamic memory allocations. - Any error-related object of any movable type is efficiently delivered to the correct error handler. - Compatible with std::error_code, errno and any other error code type. - Support for multi-thread programming. - Can be used with or without exception handling.

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Wanted to contribute in your projects
by Jibran Zia 29 Jan '19

29 Jan '19

Hello I am Jibran Zia studying in National University of Information and Technology. I wanted to contribute in your projects for 2019 Google summer of Code. Please give me general overview about how I start working and from where I get code of your projects and how I will contribute in it... Thank you so much

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GSOC 19
by Amit Singh 29 Jan '19

29 Jan '19

Hi Sir/Ma'am, My name is Amit Singh and I'm 2nd year CS student. 1. Extending GSoC 18 boost stats idea with regression model and tools for statistics. 2. Expression solver 3.Some features of functional programming similar to transform in c++ which could help programmer to apply functions to whole matrix or vector or transform the data.

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Re: [boost] [histogram] discussion of accessor interface design
by Bjorn Reese 28 Jan '19

28 Jan '19

On 1/15/19 12:35 PM, Hans Dembinski via Boost wrote: > Pros: > - really terse > - you can access methods on the pointee with x->method() as well! (useful when histogram counters are not PODs) > - you can iterate over x to get the indices, for (auto i : x) { … } works Doesn't range-for use operator* so you will get the values? > - since x acts like an array to the indices, you can pass it to functions which accept ranges or iterators (it has .begin() and .end()) > - x can be (and is) enhanced with other useful methods > * x.bin(N) returns the current bin interval for the N-th axis, allowing you to access the central value, width, edges > * x.density() returns the current density (bin value divided by product of current bin widths) > Cons: > - *x and x[0] do completely different things: *x gives you the bin value, x[0] gives you the first index An alternative is to rename x[i] to x.index(i).

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UBSan question
by Raffi Enficiaud 25 Jan '19

25 Jan '19

Hi, I am trying to correct for the errors reported by UBSAN in boost.test. A lot of them were false positive, as ... in boost.test, we check the capacity of the framework to catch various errors in the program. I compile/run the tests with the following: ../../../b2 \ --toolset=clang \ cxxflags=-std=c++11 \ cxxflags=-fno-omit-frame-pointer \ cxxflags=-fsanitize=undefined \ cxxflags=-fno-sanitize-recover=undefined \ cxxflags=-fsanitize-recover=integer-divide-by-zero \ cxxflags=-fsanitize-recover=float-divide-by-zero \ linkflags=-fsanitize=undefined \ linkflags=-fno-sanitize-recover=undefined \ linkflags=-fsanitize-recover=integer-divide-by-zero \ linkflags=-fsanitize-recover=float-divide-by-zero \ linkflags=-fuse-ld=gold \ variant=debug I have an exception that is failing the tests on clang-6/ubuntu18.04 (UBSAN exiting the process), but not on gcc-8/ubuntu18.04 (full log below). UndefinedBehaviorSanitizer:DEADLYSIGNAL ==8303==ERROR: UndefinedBehaviorSanitizer: FPE on unknown address This FPE is happening for instance after reading from a null pointer. I've searched on how to silence/blacklist this, but none of the approaches worked so far, and I am not sure what is provoking this FPE. Is there any UBsan specialist? Does anyone have an idea? Thanks, Raffi clang-linux.compile.c++.without-pch ../../../bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/prg_exec_monitor-ts/system-exception-test.o clang-linux.link ../../../bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test testing.capture-output ../../../bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test.run ====== BEGIN OUTPUT ====== prg_exec_monitor-ts/system-exception-test.cpp:38:15: runtime error: division by zero #0 0x42d03f (/home/bambooagent/bamboo-agent-home/xml-data/build-dir/RS-BCB187-CLAN/library/bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test+0x42d03f) #1 0x42f344 (/home/bambooagent/bamboo-agent-home/xml-data/build-dir/RS-BCB187-CLAN/library/bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test+0x42f344) #2 0x42e8b1 (/home/bambooagent/bamboo-agent-home/xml-data/build-dir/RS-BCB187-CLAN/library/bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test+0x42e8b1) #3 0x43dafa (/home/bambooagent/bamboo-agent-home/xml-data/build-dir/RS-BCB187-CLAN/library/bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test+0x43dafa) #4 0x43a6f2 (/home/bambooagent/bamboo-agent-home/xml-data/build-dir/RS-BCB187-CLAN/library/bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test+0x43a6f2) #5 0x436d13 (/home/bambooagent/bamboo-agent-home/xml-data/build-dir/RS-BCB187-CLAN/library/bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test+0x436d13) #6 0x43726f (/home/bambooagent/bamboo-agent-home/xml-data/build-dir/RS-BCB187-CLAN/library/bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test+0x43726f) #7 0x42d148 (/home/bambooagent/bamboo-agent-home/xml-data/build-dir/RS-BCB187-CLAN/library/bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test+0x42d148) #8 0x42e216 (/home/bambooagent/bamboo-agent-home/xml-data/build-dir/RS-BCB187-CLAN/library/bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test+0x42e216) #9 0x7f648e20fb96 (/lib/x86_64-linux-gnu/libc.so.6+0x21b96) #10 0x405859 (/home/bambooagent/bamboo-agent-home/xml-data/build-dir/RS-BCB187-CLAN/library/bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test+0x405859) UndefinedBehaviorSanitizer:DEADLYSIGNAL ==8303==ERROR: UndefinedBehaviorSanitizer: FPE on unknown address 0x00000042d049 (pc 0x00000042d049 bp 0x7ffe501ec660 sp 0x7ffe501ec630 T8303) #0 0x42d048 (/home/bambooagent/bamboo-agent-home/xml-data/build-dir/RS-BCB187-CLAN/library/bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test+0x42d048) #1 0x42f344 (/home/bambooagent/bamboo-agent-home/xml-data/build-dir/RS-BCB187-CLAN/library/bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test+0x42f344) #2 0x42e8b1 (/home/bambooagent/bamboo-agent-home/xml-data/build-dir/RS-BCB187-CLAN/library/bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test+0x42e8b1) #3 0x43dafa (/home/bambooagent/bamboo-agent-home/xml-data/build-dir/RS-BCB187-CLAN/library/bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test+0x43dafa) #4 0x43a6f2 (/home/bambooagent/bamboo-agent-home/xml-data/build-dir/RS-BCB187-CLAN/library/bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test+0x43a6f2) #5 0x436d13 (/home/bambooagent/bamboo-agent-home/xml-data/build-dir/RS-BCB187-CLAN/library/bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test+0x436d13) #6 0x43726f (/home/bambooagent/bamboo-agent-home/xml-data/build-dir/RS-BCB187-CLAN/library/bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test+0x43726f) #7 0x42d148 (/home/bambooagent/bamboo-agent-home/xml-data/build-dir/RS-BCB187-CLAN/library/bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test+0x42d148) #8 0x42e216 (/home/bambooagent/bamboo-agent-home/xml-data/build-dir/RS-BCB187-CLAN/library/bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test+0x42e216) #9 0x7f648e20fb96 (/lib/x86_64-linux-gnu/libc.so.6+0x21b96) #10 0x405859 (/home/bambooagent/bamboo-agent-home/xml-data/build-dir/RS-BCB187-CLAN/library/bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test+0x405859) UndefinedBehaviorSanitizer can not provide additional info. ==8303==ABORTING EXIT STATUS: 1 ====== END OUTPUT ====== (failed-as-expected) ../../../bin.v2/libs/test/test/system-exception-test.test/clang-linux-6.0.0/debug/threading-multi/visibility-hidden/system-exception-test.run

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Any interest in Compile Time Hash Containers library?
by Ivan Matek 25 Jan '19

25 Jan '19

Hi everybody, my first message, I hope I do not mess this up. I was contemplating writing a Compile Time Hash Containers library and I wrote a test implementation for sets and benchmarked it against mostly ska:: sets since they are the best. Document is here: https://docs.google.com/document/d/1IsUiWl3K0h2pgttYgMt67CxgJ3zeXBKZEA7hvAQ… It is quite long, but it aims to provide a introduction to the problem for people unfamiliar with details of hashing, and also it goes into a lot of discussions, if you care just about the numbers you can skip the "boring parts". My interpretation of benchmarks is that it performs very well in some cases, decently in others, but I am biased. :) Code is not available online since I do not want to dump a test project online without extensive documentation, but if somebody has a problem that may be benefited by this test implementation feel free to let me know, I would be happy to get some real world feedback on prototype. Limitations is that test implementation only works for sets, so no maps and if your objects are not integers you will probably not get much speedup. Also if your set has more than 100ish items GCC will run out of memory and VC++ does not compile code at all, so clang is the only way for most use cases today. One more disclaimer is that I do not want this library to be some beast like ranges that takes years to implement, so if after reading the document you consider implementation quite basic I won't be offended :) In other words I feel that library like this although relatively simple compared to regular Boost libraries can provide quite a lot of benefit for some usecases where people really really care about performance of hash containers where values are known during compile time. I know you can not predict the future of an unimplemented library, but I would be happy with some general feedback, and if you think this library would be nice boost proposal I would be interested in some pointers wrt how to proceed. If somebody wonders how user code looks at the moment: #include "cxhash_set.h" // also could be a result of constexpr function, no need for initializer list static constexpr std::array<int, 20> ints{0,1,2,3,5,8,21,34,64,128,256,512,1024,1701,1729,2048,4096,12345,123456,1234567}; int main() { cxhash_set<ints> ints_set; // contains could(should be?) static, but for now it is "normal" member fn std::cout << std::boolalpha << ints_set.contains(21) << std::endl; std::cout << std::boolalpha << ints_set.contains(22) << std::endl; } P.S. feel free to comment in the google doc, I actually find mailing lists quite limited when it comes to prolonged and or detailed discussions. Maybe we can ping Alexandrescu for an instance of dlang forums, so we get a better discussion tools, and he gets a way to convert us to D. :)

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