May 2008 - Boost - lists.boost.org

future .vs. Join, is "future" a form of message passing?
by Yigong Liu 16 May '08

16 May '08

Hello, Here are some thoughts i had during studying N2561 and future proposals. Please correct. Before diving into "future". Let's clarify a little bit about what is Join. Join's core primitives (async/synch/chord/actor) are for synchronization of threads and orchestration of async events. Executor(thread pool) is only one (the first) application built on top of Join's primitives which helps developing samples, but is not a intrinsic part of Join (Cw doesnt use thread pool, we also could use Asio's main threads as executor which has been described in Join's design doc) Now let's see what is a (plain-vanilla) "future": 1> in Braddock's doc: a special variable with undefined value at creation, can be set later by another thread, any attempt to get future's value will be blocked if it is not set yet. 2> in terms of N2561 proposal: "... a kind of return buffer that takes a value (or an exception) in one (sub-)thread and provides the value in another (controlling) thread. This buffer provides essentially two interfaces: * an interface to assign a value as class promise and * an interface to wait for, query and retrieve the value (or exception) from the buffer as classes unique_future and shared_future." >From both documents, future has 2 interfaces with diff behaviour: * the promise<T> interface is "asynchronous": the thread which sets the future's value will not wait for future's reader; it just sets the value and go * the future<T> interface is "synchronous": the thread which gets/reads the future's value will block wait if the future is not set yet We can define these 2 interfaces with Join as following: template<typename T> class promise_intf { public: async<void(T)> set; }; template <typename T> class future_intf { public: synch<T()> get; } A future class and its synchronization between promise_interface and future_interface can be defined as following: template <typename T> class future : public promise_intf<T>, public future_intf<T>, public actor { public: future() { chord(get, set, &future::get_result); } private: T get_result(synch_o<T()> g, async_o<void(T)> s) { return s.arg1; } }; Manually crafted future is normally implemented using one mutex and one condition var. The rule to get the number of (mutex, cond) used by a Join class is simple: each actor holds a mutex which is shared by all code in async/synch/actor, each synch<> method holds a conditional var and async<> methods hold nothing. So the above future class use exactly one mutex and one conditional var, the same as manually crafted. To transfer both result value and exception, we need use a result holder and a diff promise interface: template <typename T> class result { public: shared_ptr<T> value; exception_ptr except; ... }; template <typename T> class promise_intf { protected: async<void(result<T> r)> set_result; public: void set(T t) { set_result(result<T>(t)); } void fail(exception_ptr e) { set_result(result<T>(e)); } }; The future class will be modified as following: template <typename T> class future : public promise_intf<T>, public future_intf<T>, public actor { public: future() { chord(get, set_result, &future::get_result); } private: T get_result(synch_o<T()> g, async_o<void(result<T>)> res) { if(res.arg1.except) rethrow_exception(res.arg1.except); return res.arg1.value; } }; Again this class uses one mutex and one cond var. If we step back from the mental image of treating "future" as "a special kind of variable" for now, we can treat promise (future-setter) interface as message sending interface, and treat future_intf (future-reader) interface as message receiving interface. Then "future" becomes a message passing channel between the thread which produces and sets future's value and the thread which consumes future's value. Message sending and promise have the same behavior (async, send and go); and message recving and future_intf have the same behaviour (blocking wait). Also the above first future definition is exactly the same as the simplest message queue defined in Join: template <typename T> class queue { public: async<void(T)> send; synch<T()> recv; queue() { chord(recv, send, &queue::forward); } private: T forward(synch_o<T()> r, async_o<void(T)> s) { return s.arg1; } }; The following code is from Braddock's JobQueue: template <class T> future<T> schedule(boost::function<T (void)> const& fn) { boost::mutex::scoped_lock lck(mutex_); promise<T> prom; // create promise q_.push_back(future_wrapper<T>(fn, prom)); //queue the job condition_.notify_all(); // wake worker thread(s) return future<T>(prom); // return a future created from the promise } This code presents a very interesting idiom: we first create future (inside promise<T>'s constructor) - the message channel. Then we bundle the work item up with prom - the sending-interface of channel together, and pass this bundle to worker thread. (Asynchronously the worker thread will do the work and write the result to the sending-interface of channel). Finally we return future_intf - the receiving-interface of channel to the receiving thread. Here we have loose-coupling: worker thread don't care where the request come from and the receiver don't care who sends the result. Bundling a response-channel with a request message is the normal way how function-call or RPC call are implemented in message passing systems. It also shows another intrinsic property of message passing: using channels to define interfaces between modules and threads to achieve loose-coupling. If we can wrap around our mind and think of "future" as a form of message passing, we can gain much freedom from traditional concept of "future", for example: * we can simply bundle a reference to an async method (channel) with request; and worker thread will return result by invoking the async method when work item is done. * the receiving thread can wait-for/handle the result differently: . we can block the thread at the "getting" point, same as the current "future" implementation; . Or if the system is already message passing based (we have a main-loop to receive and process messages), and the work item request is probably sent from a message handling function to worker threads, then we can simply create a new chord which adds the response channel (async method) to the set of channels handled by the main-loop and go back to blocking wait at and serve main-loop; . Or if the application is driven by thread-pool, we can create a chord to dispatch the result from response channel to thread-pool to handle it asynchronously. Treating future as message passing also make it easier to implement wait_any_future and wait_all_future. template <typename T1, T2, T3...> class wait_all_future : public actor { public: async(void(T1)> promise1; async(void(T2)> promise2; async(void(T3)> promise3; ... synch<tuple<T1,T2,T3,...>()> wait; wait_all_future() { chord(wait, promise1, promise2, ..., &wait_all_future::proc); } private: tuple<T1,T2,T3,...> proc(synch_o<tuple<T1,T2,T3,...>()> w, async_o<void(T1)> p1, async_o<void(T2)> p2, ...) { return tuple<T1,T2,..>(p1.arg1, p2.arg1,...); } }; Applications can instantiate one wait_all instance, bundle its async response channels (promise1,promise2,...) with diff requests to diff worker threads, and then call wait(), blocking wait untill all results come back. template <typename T1, T2, T3...> class wait_any_future : public actor { public: async(void(T1)> promise1; async(void(T2)> promise2; async(void(T3)> promise3; ... synch<void()> wait; wait_any_future() { chord(wait, promise1, &wait_any_future::proc_future1); chord(wait, promise2, &wait_any_future::proc_future2); ... } private: void proc_future1(synch_o<void()> w, async_o<void(T1)> p1) { ... process p1.arg1 ... } void proc_future2(synch_o<void()> w, async_o<void(T2)> p2) { ... process p2.arg1 ... } ... }; Applications can instantiate one wait_all instance, bundle its async response channels (promise1,promise2,...) with diff requests to diff worker threads, and then call wait() in a loop, any results coming back will be processed in the order it arrives. Sorry for the long-long email. Any comments? corrections? Thanks Yigong

4 4

File System - unicode support
by Enda Mannion 16 May '08

16 May '08

Hi, I am trying to use boost filesystem. wchar_t* file = L"myfile"; boost::filesystem::path path(file); but boost can not seem to find wide character versions of the file system functions and constructors I am using. Does boost filesystem support wide character. I am compiling this on linux and on Windows. Thanks, Enda

5 8

[Filesystem] asymmetry between path(Iter, Iter) and begin/end ??
by Frank Birbacher 16 May '08

16 May '08

Hi! I'm wondering about the rationale regarding the following: path p1 = ...; path p2(p1.begin(), p1.end()); //ERROR?? How could it be the begin/end pair cannot be used to construct a new path because the value_types are way different? I want to construct a path from, for instance, a vector<string>. I can't do so easily. Regards, Frank

1 0

[shifted_ptr] Decent TLH pool added
by Phil Bouchard 16 May '08

16 May '08

Greetings: I was investigating a library called Nedmalloc which seems to offer exactly the functionality I was looking for. It's a local heap allocator, very flexible, clean, but most importantly portable. I have added the nedmalloc.h, nedmalloc.c and malloc.c.h in my sandbox under boost/detail and example/. The dedicated example tlh_pool_test1.cpp works in Windows but I haven't included the interface into the new tlh_pool.hpp file yet. Furthermore if_from() will need to be implemented because Nedmalloc doesn't offer some lookup over the list of segments to match a pointer to. There is a function called segment_holding() that will need to be wrapped by some mspace_holding(). Any pool gurus are welcome to criticize Nedmalloc or anything else before I use it. Regards, -Phil

1 1

customizable std::vector item name
by Chris Weed 15 May '08

15 May '08

Hi, I am interested in using the xml serialization code for std::vector, but currently it is hard-coded to name items, "item". Is this customizable by overloading/specializing make_nvp for my type to replace "item" with a type-specific name? I tried the following code which didn't accomplish this. Chris #include <boost/archive/xml_iarchive.hpp> #include <boost/archive/xml_oarchive.hpp> #include <boost/serialization/vector.hpp> #include <sstream> #include <iostream> struct Bob { int i; }; namespace boost { namespace serialization { /** * Try to rename items in vector<Bob> */ template<> inline const nvp<Bob> make_nvp<Bob>(const char * name,Bob& e) { return nvp<Bob>("Bob", e); } template<class Archive> void serialize(Archive& ar, Bob& v, const unsigned int version) { ar & boost::serialization::make_nvp("i",v.i); } }} int main() { Bob b; b.i = 2; std::vector<Bob> e(1); e[0] = b; std::stringstream ss; { boost::archive::xml_oarchive oa(ss); oa << boost::serialization::make_nvp("Bobs",e); } std::cout << ss.str() << std::endl; return 0; } I would like this to print the following: <?xml version="1.0" encoding="UTF-8" standalone="yes" ?> <!DOCTYPE boost_serialization> <boost_serialization signature="serialization::archive" version="4"> <Bobs class_id="0" tracking_level="0" version="0"> <count>1</count> <item_version>0</item_version> <Bob class_id="1" tracking_level="0" version="0"> <i>2</i> </Bob> </Bobs> </boost_serialization>

2 1

Trac open bugs - by assignee
by Marshall Clow 15 May '08

15 May '08

[ 311 open bugs today, 310 yesterday ] If you are maintaining a library, and have not logged into the trac system at <http://svn.boost.org/trac/boost/>, please do so ASAP. Until you do that, no tickets can be assigned to you, and will remain under "None". Instructions on working with tickets can be found at: <http://svn.boost.org/trac/boost/wiki/TicketWorkflow> and a mapping of user names to "real names" can be found at: <http://svn.boost.org/trac/boost/report/16> Bug summary 33 djowel 26 az_sw_dude 25 dgregor 22 grafik 19 dave 18 vladimir_prus 16 bemandawes 12 ramey 12 no-maintainer 12 agurtovoy 11 turkanis 11 jsiek 11 anthonyw 9 rogeeff 9 nesotto 5 igaztanaga 4 witt 4 pavol_droba 4 kaalus 4 johnmaddock 4 ebf 4 danieljames 4 None 3 samuel_krempp 3 nasonov 2 troyer 2 shammah 2 marshall 2 jmaurer 2 jano_gaspar 2 hkaiser 2 garcia 2 danielw 1 urzuga 1 t_schwinger 1 speedsnail 1 matias 1 gmelquio 1 fcacciola 1 dlwalker 1 aaron_windsor 1 <Blank> <Blank> 1750 Autolink library name not in sync with actually build lib None 1736 Headers containing non ASCII characters cause MS VC to issue warning 4819 in some locales None 1900 Missing documentation for mpl::print in the MPL library None 1901 Missing documentation for mpl::for_each in the MPL library None 1907 name of library files on mingw aaron_windsor 1622 Adjacency list needs to handle self-edges correctly agurtovoy 1001 gcc 4.1.2 segfaults on mpl/test/apply.cpp agurtovoy 1051 MPL header ordering triggers bug agurtovoy 1099 unable to iterate through a "non-explicitly-declared" mpl::set agurtovoy 1215 Boost 1.34.1_ mpl: Wrong workaround detection using MinGW32 (or.hpp_ line #33) agurtovoy 1317 has_xxx randomly broken in msvc agurtovoy 1469 [mpl] nested typedef of set has two different meanings agurtovoy 1476 always<> is not nullary. agurtovoy 1528 g++ 4.3.0 reports error because of redeclaration of next agurtovoy 1549 Boost.MPL: 'index_of' algorithm is not documented agurtovoy 1568 duplicate include guards agurtovoy 1916 [mpl] MPL_HAS_XXX_TRAIT_DEF bug in MSVC71 agurtovoy 588 mpl::remove compile error with gcc 4.1.0 anthonyw 1154 tss destruction segfaults in conjunction with dlopen/dlclose anthonyw 1168 [thread] tss crashes randomly anthonyw 1268 xtime_cmp changes to deal with overflow were reverted anthonyw 1470 Boost.Thread: Compilation errors with non-__cdecl calling convention anthonyw 1805 thread creation crashes with /Zp1 switch in VS2005 compiler anthonyw 1813 Signed/Unsigned warning in win32/condition_variable anthonyw 1825 thread.hpp injects windows.h and breaks user application. anthonyw 1826 Auto detection of threadapi and target-os broken under cygwin gcc anthonyw 1867 Missing member functions in shared_mutex (win32) anthonyw 876 xtime documentation incomplete anthonyw 881 errors when build with Apache stdcxx az_sw_dude 1028 typo in boost header: date_time/time_defs.hpp az_sw_dude 1078 from_iso_string cannot read the output from to_iso_string az_sw_dude 1098 Urgent libboost-date-time1.33.1 : bugs on ia64 ? az_sw_dude 1147 date_time library contains global #define ERROR az_sw_dude 1160 warning: month_format shadows a member of this az_sw_dude 1162 warning: ticks shadows a member of this az_sw_dude 1289 posix_time::time_facet forgets to pass a_ref argument to base class az_sw_dude 1299 change in typedef stringstream_type in format_date_parser.hpp causing compilation error az_sw_dude 1306 invalid docbook in date_period.xml az_sw_dude 1384 Linking problem with date_time library on Visual C++ 2008 Express az_sw_dude 1524 format_date_parser.hpp(221) : cannot convert parameter 1 az_sw_dude 1574 operator<< for boost::posix_time::ptime ignores ostream flags az_sw_dude 1674 date_time::date_formatting.hpp: incorrectly formats year using global locale az_sw_dude 1695 add correct namespace to class to fix compilation bug az_sw_dude 1726 boost/date_time/posix_time/time_formatters.hpp incorrectly formats fractional seconds using global locale az_sw_dude 1740 date_time includes <windows.h> az_sw_dude 1788 local_time::local_time_period streaming operators not implemented az_sw_dude 1859 boost::gregorian::to_tm() doesn't fill in tm_zone on Mac OS X az_sw_dude 1878 Documention Corrections - Various date_time Pages az_sw_dude 1903 [date_time] - 1.34+ c_local_adjustor derefs null pointer for dates >2038 az_sw_dude 287 wrong usage of ios_base::narrow az_sw_dude 316 date_time type conversion warning az_sw_dude 604 from_ftime incorrectly processes FILETIME filled with zeros az_sw_dude 642 operator<< for gregorian::date_duration not found az_sw_dude 889 Insane Dependencies az_sw_dude 890 date_time library supports only the current dst rule bemandawes 1378 filesystem path invalid name for hidden files (LINUX) bemandawes 1389 filesystem::ostream << boost::format generates operator ambigious error (in MSVC++) bemandawes 1458 Darwin Tiger throws std::runtime_error: locale::facet::_S_create_c_locale name not valid bemandawes 1578 bug in readdir_r_simulator() in a multi-threaded environment bemandawes 1583 Serious flaw in boost::filesystem filename handling (opensuse) bemandawes 1589 [filesystem] 'mbstate_t' : is not a member of 'std' bemandawes 1606 filesystem/src/exception.cpp doesn't build with gcc bemandawes 1613 Link Errors against file_system on OS X with Intel Version 10.1 C++ compilers bemandawes 1682 path_traits needs imbue() bemandawes 1701 boost::filesystem::remove_all - segmentation fault with wpath on Linux bemandawes 1711 Boost Serialization export facility broken on gcc 4.1_ 4.2 bemandawes 1767 missing file: boost/filesystem/cerrno.hpp bemandawes 1768 system: error_code.cpp #defines macros without checking whether already defined bemandawes 1840 name check functions have different behavior wrt empty string bemandawes 1876 portable_file_name() returns true for '.' and '..' bemandawes 752 directory_iterator doesn't work with catch danieljames 1554 When BOOST_HASH_NO_EXTENSIONS is defined hash doesn't support new string types. danieljames 1555 When BOOST_HASH_NO_EXTENSIONS is defined hash doesn't support boost::system::error_code danieljames 1742 Some bugs in http://www.boost.org/doc/libs/1_35_0 danieljames 1743 Documentation has incorrect Build & Link settings for some libraries danielw 1054 Parameter takes an "infinite" amount of time to compile with the Intel compiler. danielw 1097 keyword.hpp generates many warnings C4180: qualifier applied to function type has no meaning; ignored dave 1010 linking boost.python on freebsd dave 1019 iterator_facade::pointer should be the return type of operator-> (DR 445) dave 1085 Python rules for compiling in Mac OS X dave 1179 [boost.python] can not export a union in VC2005sp1 dave 1181 [boost.python] can modify enum value dave 1387 Review / update docs to reflect changes dave 1460 Python classes with multiple bases are convertible only to the first class in the lists dave 1482 boost::python::throw_error_already_set should be marked noreturn dave 1516 [python] Failing VC9 regression tests dave 1599 [python] '_set_se_translator': identifier not found dave 1697 [utility][noncopyable] ADL barrier broken by msvc-9.0 dave 1730 No debug libs on Windows by default dave 1744 [getting started] No information on building static libraries with bjam under Windows dave 1851 Issue with proxies and rvalues dave 1860 zip_iterator::value_type should not be reference dave 1887 [doc] input_iterator_archetype is not a valid InputIterator dave 1890 Missing parameters in example code dave 865 Use of C++0x keyword as identifier dave 910 gcc strict-aliasing problems with python dgregor 1009 Improper overflow handling in shortest paths algorithms dgregor 1021 [Graph][reverse_graph] Problem using reverse_graph adapter with an adapted user defined graph dgregor 1076 compile error: disconnecting struct with operator()() doesn't work in VS2005 SP1 dgregor 1164 Floyd Warshall broken with unsigned edge weights dgregor 1192 [boostbook] problem when two files have the same name dgregor 1199 configure doesn't work with path containing whitespaces (MacOS X) dgregor 1310 [result_of] const-qualified function pointer doesn't work dgregor 1326 Unable to check graph isomorphism using LEDA adapter dgregor 1391 dominator_tree_test on Borland/CodeGear outputs overly long line dgregor 1630 gcc-4.3: adjacency_list.hpp includes deprecated header dgregor 1910 function::swap should avoid doing memory allocations dgregor 1917 Boost.Signals crashes on MSVC9.0 with _HAS_ITERATOR_DEBUGGING=0 dgregor 375 LEDA graph adaptors do not handle hidden nodes properly dgregor 402 random_vertex/random_edge are unnecessarily inefficient dgregor 403 Document copy_component dgregor 447 reverse_graph and constness of property maps dgregor 556 Bundled graph properties dgregor 708 Dijkstra no_init version should not require VertexListGraph dgregor 732 Johnson All-Pairs needs better "no path" information dgregor 733 Numbered headers don't work with "preferred" syntax dgregor 735 Fruchterman-Reingold grid performance can be improved dgregor 736 Const correctness violation dgregor 738 Memory leaks with signal::connect? dgregor 829 Implicit graph not implement dgregor 852 Problem with Boost and GCC 4.1 djowel 1170 Emit Warnings instead of # symbols in the syntax highlighter djowel 1171 Quickbook title output djowel 1172 non-utf djowel 1176 Space after inline code djowel 1206 Escaping from within code? djowel 1273 CR+LF newlines in position_iterator djowel 1276 spirit problem with _GLIBCXX_DEBUG djowel 1277 Closing section like [pre with } causes Quickbok to crash djowel 1280 sections in imported source files get put inside <para> elements in docbook output djowel 1281 Quickbook produces invalid BoostBook/DocBook XML djowel 1324 tuple should have a swap() that operates element-by-element djowel 1396 wrong result_of invocation around transform_view djowel 1436 [quickbook] inline code inside headings djowel 1484 Quickbook produces illegal docbook for some docinfo fields. djowel 1500 [Spirit/Phoenix] C4512 Compiler warnings from VC8 djowel 1570 Some boost headers aren't ready for gcc 4.3 djowel 1600 duplicate include guard djowel 1601 distane of boost::tuple djowel 1607 Tuple Library Documentation Changes djowel 1610 [MSVC/STLport] [tree/common.hpp] Standard library requirements violation(incomplete type as vector parameter) djowel 1614 vector workaround needed for MSVC9 djowel 1617 spirit gcc-4.3 fix djowel 1619 [Fusion] C4512 warnings from VC9 (Visual Studio 2008) djowel 1651 incorrect typedefs in examples djowel 1763 wrong AST when parser_tag==0 djowel 1764 wrong AST when parser_tag==0 djowel 1844 Quickbook matches forward slashes (for italics) with slashes in links djowel 1864 [Documentation]There is no documentation for repetivive_view djowel 1872 [Spirit2] 'assignment operator could not be generated' warnings from VC9 djowel 1891 quickbook executable receives <dependency> djowel 1892 boost::spirit::static_ causes link error (using wave) djowel 1893 Documentation Corrections to map.html djowel 1894 fusion\support\tag_of.hpp_ boost::fusion::traits dlwalker 613 boost/crc.hpp uses non-standard conforming syntax ebf 1507 [variant] C4512 warnings from VC8.0 ebf 1548 [variant][docs]typo: formal arg_ operand_ should be v in times_two arglist ebf 1654 recursive variants do not handle nested variants correctly. ebf 993 Variant should use least common multiple of alignments_ rather than maximum fcacciola 1666 Visualizer for boost::optional garcia 1581 Boost.MultiArray: Resizing bug if the index is not 0-based garcia 1741 Review schedule out of date gmelquio 1886 Typo in Interval documentation grafik 1041 Cygwin requires PATH setting. grafik 1322 trac rejects patch attachment as spam grafik 1406 Understanding the Tables outdated grafik 1417 Regresson tests hang in Darwin (Tiger) grafik 1430 Regression fails under Cygwin grafik 1433 Trac's spam detection rejects too many valid messages grafik 1512 Broken link to vacpp in bjam docs. grafik 1513 Broken link to bcpp in bjam docs. grafik 1576 cannot read non-ASCII output messages grafik 1577 Some commands don't work because hStdInput == 0 grafik 1663 build.bat cannot set/reset ERRORLEVEL grafik 1733 Website layout overlays on IE7 grafik 1735 [website] Wrong HTML on main documentation page. grafik 1738 Boost Jam details and download link grafik 1739 Search box and Google link grafik 1753 Python docs: bad link to the Jamroot grafik 1771 Statechart TOC mangled. grafik 1776 Documentation page renders incorrectly in Safari 3.1 on OS X grafik 1906 Trac site too hard to find grafik 616 Boost Jam_ and non english directorys grafik 959 linking fails when Boost is compiled with STLport 5.1.* on Linux (names mismatch) grafik 986 Problem building Python modules on boost 1.34.0 hkaiser 1079 boost-1.34.0 fails to compile. concept checks not satisfied. hkaiser 1670 wave almost unusably slow on real-world input igaztanaga 1080 boost::interprocess win32 global file mapping issue igaztanaga 1210 interprocess::barrier hangs during second use under linux (boost 1.33.1) igaztanaga 1390 Interpocess: managed shared memory failing completely under OS X igaztanaga 1634 boost::interprocess::vector cannot contain volatile int igaztanaga 1635 Incomplete include guard in boost/intrusive jano_gaspar 1852 copy constructor does not copy capacity jano_gaspar 1919 Default constructed circular buffer throws std::bad_alloc jmaurer 351 Diff in state of mersenne_twister gen between GCC3.41 & CW9 jmaurer 599 uniform_01 copies engine instead of using a reference johnmaddock 1081 Empty string rejected as perl-style regex johnmaddock 1446 POSIX API doesn't use C locale johnmaddock 1451 error: use of C99 long long integer constant johnmaddock 1863 Boost.Regex unstable with Borland Turbo C++ 2006 jsiek 1531 segfault in dynamic_bitset::reference assign operator jsiek 1540 Poisson distribution very slow for large mean (and may also overflow). jsiek 1755 Boost.tokenizer is broken for wide characters - patch attached jsiek 1798 met an error using boost::tokenizer in multi-times in vs2005_ unicode jsiek 1888 Why doesn't InputIterator require that reference is convertible to value_type? jsiek 1909 Documentation is out of sync jsiek 575 Calling subgraph::global_to_local on a root graph jsiek 636 strange compiling problem for transitive_closure jsiek 815 remove_edge core dumps on self-circle jsiek 875 No iterator based constructor for adjacency_matrix jsiek 900 graphml reader namespace handling is broken kaalus 1184 property_tree assignment (operator) bug kaalus 1604 property_tree xml parser doesn't compile with gcc kaalus 1678 Boost.property_tree::read_xml does not parse UNICODE file with BOMs kaalus 1914 Boost.PropertyTree JSON parser in SVN trunk does not compile with Spirit2 changes marshall 1252 [pool] severe overhead with unaligned sizes. marshall 1854 Interval is not available as a component in the SVN system matias 1822 header dependency in boost/serialization/map.hpp nasonov 1220 lexical_cast requires RTTI nasonov 1847 Can't compile without <locale> header_ boost::lexical_cast problem nasonov 754 boost::any - typeid comparison across shared boundaries nesotto 1629 range/iterator_range.hpp bug nesotto 1675 [range] VC8 - compiler warnings when including range/array headers nesotto 1694 NDEBUG vs. BOOST_ASSERT in iterator_range.hpp nesotto 1748 [ptr_container] compiler warnings from VC9 nesotto 1754 Illegal HTML in range docs. nesotto 1785 assign::list_of works poorly with class constructors nesotto 1795 [ptr_container] minor documentation typo nesotto 1842 boost::sub_rage::front error nesotto 1908 boost::size(std::set<T> const& s) causes compile errors with msvc no-maintainer 1068 Mersenne twister disables streaming for Visual C++ no-maintainer 1222 lambda::ret<T> should declare result_type. no-maintainer 1270 uniform_smallint doesn't compile with lagged_fibonacci random number generators no-maintainer 1515 [lambda] C4512 warnings from VC8.0 no-maintainer 1544 uniform_01 w/ref template param causes ref to ref error no-maintainer 1546 Method boost::random::uniform_int::operator()(engine_ value) is missing no-maintainer 1572 [lambda] smart pointer const-ness affects its contents no-maintainer 1632 Default Interval rounding policies incomplete no-maintainer 1691 [Random] Brokem MSVC workaround no-maintainer 1856 minstd_rand returning different values in 1.35.0 than in 1.34.1 no-maintainer 781 Lambda: (_1 + "y")(string("x")) Doesn't Compile no-maintainer 819 uniform_int<> with type's maximum availaible range error pavol_droba 1152 rle_example fails pavol_droba 1385 begin must be boost-qualified pavol_droba 1761 StringAlgo: Error in an example pavol_droba 1827 String algorithm composite header doesn't include join ramey 1708 Can't serialize class with private destructor ramey 1734 BOOST_STATIC_WARNING can't be passed a dependent expression ramey 1747 [serialization] unreferenced formal parameter warnings from VC9 ramey 1807 boost::archive::xml_archive_exception does not store error code and reports wrong message text ramey 1812 Boost.Serialization fails to build on Cygwin ramey 1823 Archive concept: Incomplete description? ramey 1824 serialization keeps using wchar_t if BOOST_NO_STD_WSTRING is set ramey 1836 bug in serializing wide character strings ramey 1837 Base class missed in binary_wiarchive ramey 1849 Deserialization of std::string overwrites non-copied contents. ramey 1857 IA64_ GCC 4.3_ redefinition of 'struct boost::serialization::implementation_level<std::vector<long int_ std::allocator<long int> > >' ramey 1877 Documentation Corrections - Archive Concepts rogeeff 1383 signal.h features not found on Mac OS rogeeff 1542 [test] compiler errors when building with stdcxx library rogeeff 1644 Boost.Test missing documentation file BOOST_CHECK_CLOSE_FRACTION.html rogeeff 1676 Dead links on Boost.Test example documentation. rogeeff 1723 No subprocess can be started in init_unit_test_suite rogeeff 1746 Online documentation for 1.35.0 is out of date for current lib version rogeeff 1839 Test fails if child process exits with non-zero code rogeeff 1866 Typos in Boost Test documentation rogeeff 1869 Typo in Unit Test Framework documentation samuel_krempp 1699 Compile warning about initialization order. samuel_krempp 1801 Typo in documentation. samuel_krempp 859 boost::format ignores a user defined locale shammah 290 perfomance: memory cleanup for pool takes too long shammah 386 boost::pool_allocator breaks with vector of vectors speedsnail 1138 Problems with TSS and static thread library t_schwinger 1653 wave executable erroneously required for build of function_types lib troyer 1774 serialization: file written with 1.34.1 can't be read in with 1.35 troyer 1778 Possible regression in 1.35 serialization of 2D arrays turkanis 1523 [iostreams] VC8/VC9 compiler warnings turkanis 1545 [boost/rational.hpp] 'noskipws' is not a member of 'std' turkanis 1579 gzip compressor should model DualUseFilter turkanis 1580 Add static assert to prohibit instantiating a chain with mode dual_use turkanis 1649 Fix definition of JavaScript menu to avoid long chains of functions turkanis 1656 Consider implementing flush() for symmetric filters turkanis 1671 type mismatch of buffer size parameter causes overload resolution to fail turkanis 1727 Sample code in documentation does not compile_ has namespace errors. turkanis 1870 zlib_base function names must differ from their zlib counterpart turkanis 1875 Boost.Iostreams warnings with GCC -Wall -W -std=c++98 -pedantic turkanis 1896 boost::iostreams::gzip_decompressor silently ignores multiple members urzuga 574 [boost::lambda] Compile error with libstdc++ debug mode vladimir_prus 1132 program_options documentation error. vladimir_prus 1165 more quoting problems vladimir_prus 1274 Useless error message vladimir_prus 1527 [program_options] Second (and subsequent) lines in tabbed text not aligned correctly vladimir_prus 1530 Program options documentation - Overview - Syntactic Information example typo vladimir_prus 1537 no value given in 'mysql_password =' vladimir_prus 1584 cryptic bbv2 error building quickbook vladimir_prus 1587 [program_options] crashes if value part missing in external configuration file vladimir_prus 1588 [program_options] crashes if value part missing in external configuration file vladimir_prus 1645 Invalid unicode support for default_value vladimir_prus 1679 added 4-way universal binary support from mac osx (ppc_ ppc64_ i386_ x86_64) vladimir_prus 1809 Allow empty values in conf file vladimir_prus 1880 documentation bug vladimir_prus 1904 undefined reference to `boost::program_options::options_description::m_default_line_length' vladimir_prus 1911 scanner.jam needs to import module errors vladimir_prus 469 multitoken broken vladimir_prus 689 [program_options] Endless loop with long default arguments vladimir_prus 850 program_options strips off escaped quotes in some situations witt 583 Fixes for build on IBM pSeries for AIX and Linux witt 834 Homepage regression links witt 957 The "Getting Started" page does not mention the stdlib option witt 973 zip_iterator has value_type == reference -- -- Marshall Marshall Clow Qualcomm, Inc. <mailto:mclow@qualcomm.com> The famous British scientist, Lord Kelvin, said: "When you measure what you are speaking about and express it in numbers, you know something about it, but when you cannot (or do not) measure it, when you cannot (or do not) express it in numbers, then your knowledge is of a meagre and unsatisfactory kind."

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Re: [boost] [circular_buffer] default constructor usually throws std::bad_alloc
by Jan Gaspar 15 May '08

15 May '08

OK, will see what can I do with the 1.35.1. release. Btw on the 4th line I don't see a problem to explicitly set the capacity like this: circular_buffer<char> buffer(0); // nothing will be allocated ----- Original Message ---- From: Dean Michael Berris <mikhailberis(a)gmail.com> To: boost(a)lists.boost.org Sent: Thursday, 15 May, 2008 2:04:58 PM Subject: Re: [boost] [circular_buffer] default constructor usually throws std::bad_alloc On Thu, May 15, 2008 at 7:48 PM, Jan Gaspar <jano_gaspar(a)yahoo.com> wrote: > This was an intended behaviour (to allocate the maximum capacity). The reason behind this was to comply with other STL containers. I admin the decision was not the best one. I will change this as you propose but in the Boost version 1.36. For now just use the constructor with the explicit capacity paramater or override the allocator's max_size() to return some sensible value. > Actually, this is going to be really hard to do especially if you are expecting the buffer from another source and just need a default constructed "receiver" to get it: map<string, circular_buffer<char> > input_buffers; input_buffers.insert(std::make_pair("cin", circular_buffer<char>(1000))); input_buffers.insert(std::make_pair("net", circular_buffer<char>(2048))); circular_buffer<char> buffer; // this will throw string source; cin >> source; if (input_buffers.find(source) != input_buffers.end()) { buffer = input_buffers.find(source)->second; }; With the current implementation, you may not be able to get past the default constructed buffer, and if you did set some capacity, you'd be wasting memory. Shouldn't the change make it to Boost 1.35.1? :-D It's a really trivial fix for the constructor, but I haven't looked at how it will affect the other areas of the code. Thanks for the quick response! :) -- Dean Michael C. Berris Software Engineer, Friendster, Inc. [http://blog.cplusplus-soup.com] [mikhailberis(a)gmail.com] [+63 928 7291459] [+1 408 4049523] _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost __________________________________________________________ Sent from Yahoo! Mail. A Smarter Email http://uk.docs.yahoo.com/nowyoucan.html

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Re: [boost] [circular_buffer] default constructor usually throws std::bad_alloc
by Jan Gaspar 15 May '08

15 May '08

This was an intended behaviour (to allocate the maximum capacity). The reason behind this was to comply with other STL containers. I admin the decision was not the best one. I will change this as you propose but in the Boost version 1.36. For now just use the constructor with the explicit capacity paramater or override the allocator's max_size() to return some sensible value. Jan ----- Original Message ---- From: Dean Michael Berris <mikhailberis(a)gmail.com> To: "boost(a)lists.boost.org" <boost(a)lists.boost.org> Sent: Thursday, 15 May, 2008 1:17:27 PM Subject: [boost] [circular_buffer] default constructor usually throws std::bad_alloc I've attached a trivial patch to circular buffer which should allow it to be default constructed (and copy from an existing buffer) without making the default constructor cause an insane request to allocate a huge amount of memory (and fail to throw an std::bad_alloc). I personally think this is a show stopper bug in Boost 1.35.0 and the patch is distributed under the Boost C++ License Version 1.0. Should this be applied to be made part of 1.35.1? -- Dean Michael C. Berris Software Engineer, Friendster, Inc. [http://blog.cplusplus-soup.com] [mikhailberis(a)gmail.com] [+63 928 7291459] [+1 408 4049523] __________________________________________________________ Sent from Yahoo! Mail. A Smarter Email http://uk.docs.yahoo.com/nowyoucan.html

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[circular_buffer] default constructor usually throws std::bad_alloc
by Dean Michael Berris 15 May '08

15 May '08

I've attached a trivial patch to circular buffer which should allow it to be default constructed (and copy from an existing buffer) without making the default constructor cause an insane request to allocate a huge amount of memory (and fail to throw an std::bad_alloc). I personally think this is a show stopper bug in Boost 1.35.0 and the patch is distributed under the Boost C++ License Version 1.0. Should this be applied to be made part of 1.35.1? -- Dean Michael C. Berris Software Engineer, Friendster, Inc. [http://blog.cplusplus-soup.com] [mikhailberis(a)gmail.com] [+63 928 7291459] [+1 408 4049523]

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very poor thread performance
by James Sutherland 15 May '08

15 May '08

I have been testing thread performance on Linux and Mac. My Linux system has two dual-core processors and my Mac has one dual-core processor. Both are intel chips. For the code snippet given below, the execution time should ideally decrease as the number of threads increases. However, the opposite trend is observed. For example, using -O3 flags on my Linux desktop produces the following timings: 1 Thread: 0.66 sec 2 Threads: 0.9 sec 3 Threads: 1.2 sec 4 Threads: 1.4 sec I do not have a lot of experience with threads, and was wondering if this result surprises anyone? James ----- #include <boost/thread.hpp> #include <iostream> #include <vector> #include <time.h> struct MyStruct { explicit MyStruct(const int i) : tag(i) {} void operator()() const { const int n = 100; std::vector<int> nums(n,0); for( int j=0; j<1000000; ++j ) for( int i=0; i<n; ++i ) nums[i] = i+tag; } private: int tag; }; int main() { using namespace std; const int nTasks = 12; const int nThreads = 4; assert( nTasks%nThreads == 0 ); assert( nThreads<=nTasks ); cout << "Executing " << nTasks << " using " << nThreads << " threads." << endl; time_t t1 = clock(); for( int itask=0; itask<nTasks; ++itask ){ boost::thread_group threads; for( int i=0; i<nThreads; ++i ){ threads.create_thread( MyStruct(itask++ + 100) ); } threads.join_all(); } t2 = clock(); cout << "time: " << difftime( t2,t1)/CLOCKS_PER_SEC << endl; } ----

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