- Boost-users - lists.boost.org

Re: [Boost-users] NEWBIE: Undefined references: How do I find the library that resolves an undefined reference - Expanded with log example and hope for a general solution
by JENNINGS, LYNN M NH-03 USAF AFMC 517 SMXS/MXDPB 26 Jan '17

26 Jan '17

Thanks Richard and Andy for the timely response! Andy's answers provides the perfect example of my dilemma. When Andy said to check the MSDN documentation for ms742213, I quickly found that I needed the Ws2_32.lib library, which I was able to solve my issue. However, I also have the following: 1. boost::log::add_log_file(...) with a sinks::file::rotation_at_time_point(...) 2. boost::random::random_device range; I made a guess with the log and added boost_log_setup_mgw48-mt-d-1_61 and boost_log_ mgw48-mt-d-1_61, but these libraries didn't resolve my issue. When I check the boost documentation (I realize that many of the boost additions just require header files, which the examples are careful to specify. I figure this must require a library because I am getting an undefined error.), there were many mentions of a library, but I couldn't find where the name of the library was specified! So I hope there is a general way to determine the name of the boost library so I do not need to keeping asking about particular undefined errors. In the past, I have been able to google the undefined error and find the library reference, but Thanks again for all of your help! -----Original Message----- On 1/24/2017 3:44 PM, Richard Hodges wrote: > That would be the winsock library. > > https://msdn.microsoft.com/en-us/library/ms740673.aspx > > > > On 24 January 2017 at 20:33, JENNINGS, LYNN M NH-03 USAF AFMC 517 > SMXS/MXDPB <lynn.jennings_at_[hidden]> wrote: > >> NEWBIE question: Undefined references: How do I find the library that >> resolves an undefined reference. For example, the output for the gcc >> linker running in MinGW shows: >> >> C:/boost/boost/asio/detail/impl/winsock_init.ipp:39: Undefined reference >> to `WSAStartup_at_8' >> >> I have googled the documentation a number of ways, but I cannot find the >> library that will resolve this error. I am sure that this is a common >> problem. Please point me to the documentation so I can fix this and the >> undefined references. >> >> Thanks! In the future, you can check Microsoft's documentation [1] for info on their functions. I searched for "WSAStartup", and found [2]. At the bottom of that page is a "Requirements" box, which tells you the library it's in. Andy 1. http://msdn.microsoft.com 2. https://msdn.microsoft.com/en-us/library/windows/desktop/ms742213(v=vs.85).…

2 1

circular_buffer: rotate() vs erase_begin() for scalars
by Robert Dailey 25 Jan '17

25 Jan '17

I'm using circular_buffer to represent a FIFO queue of bytes: boost::circular_buffer<std::uint8_t> m_queue; When I read bytes from the "front", I simply do: m_queue.erase_begin(num_read_bytes); I do so because the documentation for erase_begin() specifically mentions constant time performance for scalar types since no destructor needs to be called. However, I feel that rotate() better expresses what I'm trying to do. Is there a reason to prefer one over the other for scalar types?

2 3

C++Now / BoostCon 2017 -- Call For Submissions
by Michael Caisse 23 Jan '17

23 Jan '17

This is a quick reminder that the C++Now 2017 Call For Submissions is *open*. All submissions must be made by February 3rd. For more information, see http://cppnow.org/

1 0

How to build Boost with Clang/libc++ and NOT link against libstdc++?
by Deniz Bahadir 20 Jan '17

20 Jan '17

Hi guys, I am struggling with building the Boost (1.58.0) libraries with Clang (3.8) and libc++ (on Ubuntu 16.04). I am able to build the Boost libraries using Clang and flags "-std=c++14 -stdlib=libc++", however, I noticed that several libraries are still linked against GCC's standard-library "libstdc++". I then tried adding the flag "-lc++abi" (later I tried "-Wl,-lc++abi") to Boost.Build options "cxxflags" and "linkflags" to explicitly link against "libc++abi". With no luck. Several boost-libraries are still linked against "libstdc++". Does anyone know how and why this link-dependency gets added and how to get rid of them? Does it come in through some other link-dependencies? At least none of them seem to link to "libstdc++"? The Boost shared-libraries that link to "libstdc++" are: libboost_chrono-clang38-mt-1_58_0.so.1.58.0 libboost_context-clang38-mt-1_58_0.so.1.58.0 libboost_coroutine-clang38-mt-1_58_0.so.1.58.0 libboost_date_time-clang38-mt-1_58_0.so.1.58.0 libboost_filesystem-clang38-mt-1_58_0.so.1.58.0 libboost_graph-clang38-mt-1_58_1.so.0.58.0 libboost_iostreams-clang38-mt-1_58_0.so.1.58.0 libboost_locale-clang38-mt-1_58_0.so.1.58.0 libboost_log-clang38-mt-1_58_0.so.1.58.0 libboost_log_setup-clang38-mt-1_58_0.so.1.58.0 libboost_math_tr1-clang38-mt-1_58_0.so.1.58.0 libboost_math_tr1f-clang38-mt-1_58_0.so.1.58.0 libboost_math_tr1l-clang38-mt-1_58_0.so.1.58.0 libboost_program_options-clang38-mt-1_58_0.so.1.58.0 libboost_python-clang38-mt-1_58_0.so.1.58.0 libboost_random-clang38-mt-1_58_0.so.1.58.0 libboost_regex-clang38-mt-1_58_0.so.1.58.0 libboost_signals-clang38-mt-1_58_0.so.1.58.0 libboost_thread-clang38-mt-1_58_0.so.1.58.0 libboost_timer-clang38-mt-1_58_0.so.1.58.0 libboost_unit_test_framework-clang38-mt-1_58_0.so.1.58.0 libboost_wave-clang38-mt-1_58_0.so.1.58.0 The once that are fine and do not link against "libstdc++" are: libboost_atomic-clang38-mt-1_58_0.so.1.58.0 libboost_container-clang38-mt-1_58_0.so.1.58.0 libboost_math_c99-clang38-mt-1_58_0.so.1.58.0 libboost_math_c99f-clang38-mt-1_58_0.so.1.58.0 libboost_math_c99l-clang38-mt-1_58_0.so.1.58.0 libboost_serialization-clang38-mt-1_58_0.so.1.58.0 libboost_system-clang38-mt-1_58_0.so.1.58.0 libboost_wserialization-clang38-mt-1_58_0.so.1.58.0 Interestingly, all libraries are also linked against "libc++abi" except for: libboost_atomic-clang38-mt-1_58_0.so.1.58.0 libboost_container-clang38-mt-1_58_0.so.1.5 For completeness, my build-command is this: cd /home/jenkins/workspace/Pipeline_Boost/sources/boost_1_58_0 LINK_LIBCXXABI="-Wl,-lc++abi" COMMON_COMPILER_FLAGS="-m64 -fpic -fdiagnostics-color=always -O3" CFLAGS="$COMMON_COMPILER_FLAGS" CXXFLAGS="$COMMON_COMPILER_FLAGS -std=c++14 -stdlib=libc++ -isystem/usr/include/libcxxabi $LINK_LIBCXXABI" CC=/usr/bin/clang-3.8 CXX=/usr/bin/clang++-3.8 /home/jenkins/workspace/Pipeline_Boost@3/clang38/build/boost-build/b2 -j1 -q \ --build-dir=/home/jenkins/workspace/Pipeline_Boost@3/clang38/build/boost \ --build-type=minimal --layout=versioned address-model=64 install \ --prefix=/home/jenkins/workspace/Pipeline_Boost@3/clang38/installed/opt/BENOCS/clang38 \ --libdir=/home/jenkins/workspace/Pipeline_Boost@3/clang38/installed/opt/BENOCS/clang38/lib/x86_64-linux-gnu \ dll-path==/opt/BENOCS/clang38/lib/x86_64-linux-gnu \ toolset=clang-3.8 \ cflags="$CFLAGS" CXXFLAGS="$CXXFLAGS" \ linkflags="-Wl,--as-needed $LINK_LIBCXXABI" For the environment-variable LINK_LIBCXXABI I tried "-lc++abi" as well and also tried providing it only in the cxxflags or the linkflags or both (as above). I would be happy, if anyone could explain that behavior or could even provide a workaround/fix for me, so that "libstdc++" is no longer linked. Thanks, Deniz PS: BTW, does anyone know if it is correct, that shared libraries (in general) that are linked against "libc++abi" do always also link to "libgcc_s"? (What is it for?) -- BENOCS GmbH Dipl.-Inform. Deniz Bahadir Winterfeldtstr. 21 10781 Berlin Germany Phone: +49 - 30 / 577 0004-22 Email: deniz.bahadir(a)benocs.com www.benocs.com Board of Management: Michael Wolz, Dr.-Ing. Oliver Holschke, Dr.-Ing. Ingmar Poese Commercial Register: Amtsgericht Bonn HRB 19378

2 2

Fwd: Boost coroutine/context libraries
by Gregory Laird 20 Jan '17

20 Jan '17

--------------- Forwarded message (begin) Subject: Boost coroutine/context libraries From: Gregory Laird <glaird(a)northgatebowl.com> Date: Tue, 17 Jan 2017 17:10:57 -0800 Newsgroup: gmane.comp.lib.boost.user I am trying to write a cooperative task scheduler in c++ and I have discovered the boost context and coroutine libraries. I have written these sorts of schedulers many times in assembly language so I appreciate the issues in the methodology. I have written lots of c code but am less versed in c++. I have been trying to find some straightforward examples of the libraries use without a lot of extraneous c++ language elements (e.g. binds, lambdas, etc.). I did find one example http://stackoverflow.com/questions/11716291/boost-context-class that is very nice, but it will not compile now with the current boost library. I get an error saying that boost::context::fcontext_t has been removed from the public api. Could someone direct me to some examples that demonstrate the context or coroutine functionality that would be easier to understand. I want to write a scheduler that is very similar to the example listed above where coroutines yeild back to a main caller which then chooses the next coroutine to continue its processing. Thanks. --------------- Forwarded message (end)

5 6

Program abort at canonical()
by Andy 20 Jan '17

20 Jan '17

I have: #include <boost/filesystem/path.hpp> #include <boost/filesystem/operations.hpp> boostPath = canonical(boostPath); While I debug it is OK, but when I run debug or release x64 program standalone from cmd - it abort at canonical without any info.

4 6

Multiprecision -- cubing a number gives unexpected result
by Craig Henderson 19 Jan '17

19 Jan '17

Hello, I am new to Boost.Multiprecision and have come across a result that I cannot understand. I have the following code to calculate the sum of three cubes, using bigint_t = boost::multiprecision::mpz_int; bigint_t a = 2220422932; bigint_t b = 2218888517; b = -b; bigint_t c = 283059965; c = -c; std::cout << '(' << a << ")^3+(" << b << ")^3+(" << c << ")^3 = "; bigint_t a1 = a * a * a; bigint_t b1 = b * b * b; bigint_t c1 = c * c * c; std::cout << '(' << a1 << ")+(" << b1 << ")+(" << c1 << ") = "; std::cout << bigint_t(a1+b1+c1) << '\n'; and it produces the correct result (2220422932)^3+(-2218888517)^3+(-283059965)^3 = (10947302325566084787191541568)+(-10924622727902378924946084413)+(-22679597663705862245457125) = 30 However, if I use this implementation, with a,b and c assigned the result of the multiplication, a = a * a * a; b = b * b * b; c = c * c * c; std::cout << '(' << a << ")+(" << b << ")+(" << c << ") = "; std::cout << bigint_t(a+b+c) << '\n'; ... I get a very strange result: (24307641127223864542936438774018437376)+(24240519923499804093545671548118385521)+(6419686120902663137493915211500625) = 48554580736844571299619604237348323522 What is going on? Is this an invalid use of the multiplication that I have missed? I get the same result with cpp_int and gmp; using bigint_t = boost::multiprecision::cpp_int; using bigint_t = boost::multiprecision::mpz_int; I'm using g++ (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609, Boost 1.58 Many thanks Craig

2 1

[Boost.Math] Weird compiler-error with Clang 3.8
by Deniz Bahadir 19 Jan '17

19 Jan '17

Hi guys, Our build-server (Jenkins) tried to build Boost 1.58 with Clang 3.8 and libc++ and tripped over an error that I do not understand. Maybe someone can shed some light on it? The specific error is this: clang-linux.compile.c++.pch /home/jenkins/workspace/Pipeline_Boost@3/clang38/build/boost/boost/bin.v2/libs/math/build/clang-linux-3.8/release/threading-multi/../src/tr1/pch.hpp.pth clang: error: cannot specify -o when generating multiple output files Does this look familiar to anyone? My build-environment is Ubuntu 16.04 x86_64 and I invoked Boost.Build like this: cd /home/jenkins/workspace/Pipeline_Boost/sources/boost_1_58_0 COMMON_COMPILER_FLAGS="-m64 -fpic -fdiagnostics-color=always -O3" CFLAGS="$COMMON_COMPILER_FLAGS" CXXFLAGS="$COMMON_COMPILER_FLAGS -std=c++14 -stdlib=libc++ -isystem/usr/include/libcxxabi -lc++abi" CC=/usr/bin/clang-3.8 CXX=/usr/bin/clang++-3.8 /home/jenkins/workspace/Pipeline_Boost@3/clang38/build/boost-build/b2 -j1 -q \ --build-dir=/home/jenkins/workspace/Pipeline_Boost@3/clang38/build/boost \ --build-type=minimal --layout=versioned address-model=64 install \ --prefix=/home/jenkins/workspace/Pipeline_Boost@3/clang38/installed/opt/BENOCS/clang38 \ --libdir=/home/jenkins/workspace/Pipeline_Boost@3/clang38/installed/opt/BENOCS/clang38/lib/x86_64-linux-gnu \ dll-path==/opt/BENOCS/clang38/lib/x86_64-linux-gnu \ toolset=clang-3.8 \ cflags="$CFLAGS" CXXFLAGS="$CXXFLAGS" linkflags="-Wl,--as-needed" The more detailed error-message is the following: common.mkdir /home/jenkins/workspace/Pipeline_Boost(a)3/clang38/build/boost/boost/bin.v2/libs/math/build common.mkdir /home/jenkins/workspace/Pipeline_Boost@3/clang38/build/boost/boost/bin.v2/libs/math/build/clang-linux-3.8 common.mkdir /home/jenkins/workspace/Pipeline_Boost@3/clang38/build/boost/boost/bin.v2/libs/math/build/clang-linux-3.8/release common.mkdir /home/jenkins/workspace/Pipeline_Boost@3/clang38/build/boost/boost/bin.v2/libs/math/build/clang-linux-3.8/release/threading-multi common.mkdir /home/jenkins/workspace/Pipeline_Boost@3/clang38/build/boost/boost/bin.v2/libs/math/build/clang-linux-3.8/release/threading-multi/.. common.mkdir /home/jenkins/workspace/Pipeline_Boost@3/clang38/build/boost/boost/bin.v2/libs/math/build/clang-linux-3.8/release/threading-multi/../src common.mkdir /home/jenkins/workspace/Pipeline_Boost@3/clang38/build/boost/boost/bin.v2/libs/math/build/clang-linux-3.8/release/threading-multi/../src/tr1 clang-linux.compile.c++.pch /home/jenkins/workspace/Pipeline_Boost@3/clang38/build/boost/boost/bin.v2/libs/math/build/clang-linux-3.8/release/threading-multi/../src/tr1/pch.hpp.pth clang: error: cannot specify -o when generating multiple output files rm -f "/home/jenkins/workspace/Pipeline_Boost@3/clang38/build/boost/boost/bin.v2/libs/math/build/clang-linux-3.8/release/threading-multi/../src/tr1/pch.hpp.pth" && "clang++" -x c++-header -m64 -fpic -fdiagnostics-color=always -O3 -std=c++14 -stdlib=libc++ -isystem/usr/include/libcxxabi -lc++abi -m64 -fpic -fdiagnostics-color=always -O3 -O3 -Wno-inline -Wall -pthread -fPIC -m64 -m64 -fpic -fdiagnostics-color=always -O3 -std=c++14 -stdlib=libc++ -isystem/usr/include/libcxxabi -lc++abi -m64 -fpic -fdiagnostics-color=always -O3 -DBOOST_ALL_NO_LIB=1 -DBOOST_BUILD_PCH_ENABLED -DBOOST_MATH_TR1_DYN_LINK=1 -DNDEBUG -I"." -I"libs/math/src/tr1" -Xclang -emit-pth -o "/home/jenkins/workspace/Pipeline_Boost@3/clang38/build/boost/boost/bin.v2/libs/math/build/clang-linux-3.8/release/threading-multi/../src/tr1/pch.hpp.pth" "libs/math/build/../src/tr1/pch.hpp" ...failed clang-linux.compile.c++.pch /home/jenkins/workspace/Pipeline_Boost@3/clang38/build/boost/boost/bin.v2/libs/math/build/clang-linux-3.8/release/threading-multi/../src/tr1/pch.hpp.pth... ...skipped <p/home/jenkins/workspace/Pipeline_Boost@3/clang38/build/boost/boost/bin.v2/libs/math/build/clang-linux-3.8/release/threading-multi>assoc_laguerre.o for lack of <p/home/jenkins/workspace/Pipeline_Boost@3/clang38/build/boost/boost/bin.v2/libs/math/build/clang-linux-3.8/release/threading-multi>../src/tr1/pch.hpp.pth... ...failed updating 1 target... ...skipped 1 target... ...updated 11871 targets... Can someone tell me what is going on and how to fix or work around this problem? Thanks, Deniz -- BENOCS GmbH Dipl.-Inform. Deniz Bahadir Winterfeldtstr. 21 10781 Berlin Germany Phone: +49 - 30 / 577 0004-22 Email: deniz.bahadir(a)benocs.com www.benocs.com Board of Management: Michael Wolz, Dr.-Ing. Oliver Holschke, Dr.-Ing. Ingmar Poese Commercial Register: Amtsgericht Bonn HRB 19378

3 4

Re: [Boost-users] Fwd: Boost coroutine/context libraries
by Nat Goodspeed 19 Jan '17

19 Jan '17

On Jan 18, 2017 2:39 PM, "Gregory Laird" <glaird(a)northgatebowl.com> wrote: Question: If I allocate too small of a stack, and something gets written outside of the allocation, is there any way to know that this has occurred? http://www.boost.org/doc/libs/1_63_0/libs/context/doc/html/context/stack/pr…

1 0

1.63.0: diffenre package with the same version
by Ivan Kabaivanov 16 Jan '17

16 Jan '17

Hi, first time poster here. I've been compiling boost from source for about 8 years now. I download the packages from sourceforge.net (https://sourceforge.net/projects/boost/files/boost/1.63.0/) Lately (last few releases) I notice a troubling trend -- the same package, say boost_1_63_0.tar.bz2 will have a different md5 hash if downloaded again a few weeks after being downloaded for the first time. Case in point: boost_1_63_0.tar.bz2, downloaded around Fri Dec 30 17:11:50 2016 +0200 (GMT+2) had md5 hash d17537e28aa2131fa192ce2870ce72a3. The very same file, dowloaded today (January 15, 2017) has a new md5 hash: 1c837ecd990bb022d07e7aab32b09847. What's more troubling is that a cursory comparison of the two files' contents reveals differences. To begin with, the old package had 53599 files, while the new one has 53655. Further, files that are present in both packages have small differences. $ diff -Naur ../../OLD/boost_1_63_0/./libs/numeric/odeint/doc/html/boost/numeric/odeint/base_tag.html ../../NEW/boost_1_63_0/./libs/numeric/odeint/doc/html/boost/numeric/odeint/base_tag.html--- ../../OLD/boost_1_63_0/./libs/numeric/odeint/doc/html/boost/numeric/odeint/base_tag.html 2016-12-29 17:12:21.000000000 +0200+++ ../../NEW/boost_1_63_0/./libs/numeric/odeint/doc/html/boost/numeric/odeint/base_tag.html 2016-12-22 14:47:46.000000000 +0200@@ -7,7 +7,7 @@ <link rel="home" href="../../../index.html" title="Chapter 1. Boost.Numeric.Odeint"> <link rel="up" href="../../../header/boost/numeric/odeint/stepper/stepper_categories_hpp.html" title="Header <boost/numeric/odeint/stepper/stepper_categories.hpp>"> <link rel="prev" href="dense_output_stepper_tag.html" title="Struct dense_output_stepper_tag">-<link rel="next" href="base_tag_stepp_idp64335824.html" title="Struct base_tag<stepper_tag>">+<link rel="next" href="base_tag_stepp_idp34699008.html" title="Struct base_tag<stepper_tag>"> </head> <body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> <table cellpadding="2" width="100%"><tr>@@ -20,7 +20,7 @@ </tr></table> <hr> <div class="spirit-nav">-<a accesskey="p" href="dense_output_stepper_tag.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../../header/boost/numeric/odeint/stepper/stepper_categories_hpp.html"><img src="../../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="base_tag_stepp_idp64335824.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a>+<a accesskey="p" href="dense_output_stepper_tag.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../../header/boost/numeric/odeint/stepper/stepper_categories_hpp.html"><img src="../../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="base_tag_stepp_idp34699008.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> </div> <div class="refentry"> <a name="boost.numeric.odeint.base_tag"></a><div class="titlepage"></div>@@ -45,7 +45,7 @@ </tr></table> <hr> <div class="spirit-nav">-<a accesskey="p" href="dense_output_stepper_tag.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../../header/boost/numeric/odeint/stepper/stepper_categories_hpp.html"><img src="../../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="base_tag_stepp_idp64335824.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a>+<a accesskey="p" href="dense_output_stepper_tag.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../../header/boost/numeric/odeint/stepper/stepper_categories_hpp.html"><img src="../../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="base_tag_stepp_idp34699008.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> </div> </body> </html> I know, these are trivial differences. But they are differences nevertheless and this is not acceptable for package maintainers. I've heard stories of how SourceForge is (or used to be ?) modifying packages to include crapware and sponsored content. So my first reaction was to suspect SF.net of pulling some stupid/shady stuff. But I'm beginning to wonder it it was SF.net really. Please, investigate what's happening and please fix it. As a package maintainer I can no longer vouchsafe for the integrity of the upstream package. Thanks,IvanK.

2 1