August 2006 - Boost - lists.boost.org

Re: [boost] Portable signbit macro/function?
by Martin Bonner 04 Aug '06

04 Aug '06

----Original Message---- From: boost-bounces(a)lists.boost.org [mailto:boost-bounces@lists.boost.org] On Behalf Of Peter Dimov Sent: 04 August 2006 11:39 To: boost(a)lists.boost.org Subject: Re: [boost] Portable signbit macro/function? > Johan Råde wrote: > >> I still find it hard to believe that the volatile are needed ;-) > > It is not. If volatile is not present, then you can't instantiate the template with T="volatile float" for example. (Similarly you need the "const" so that you can invoke with T="const float".) I suspect that for this application that doesn't matter, but that Gennaro was so used to using the safe form: reinterpret_cast<const volatile char*>(&s) to get at the bytes of an object in a template, that he just wrote it automatically. -- Martin Bonner Martin.Bonner(a)Pitechnology.com Pi Technology, Milton Hall, Ely Road, Milton, Cambridge, CB4 6WZ, ENGLAND Tel: +44 (0)1223 203894

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Re: [boost] Portable signbit macro/function?
by Martin Bonner 04 Aug '06

04 Aug '06

----Original Message---- From: boost-bounces(a)lists.boost.org [mailto:boost-bounces@lists.boost.org] On Behalf Of Guillaume Melquiond Sent: 03 August 2006 17:16 To: boost(a)lists.boost.org Subject: Re: [boost] Portable signbit macro/function? > Le jeudi 03 août 2006 à 17:49 +0200, Johan Råde a écrit : > >> All I need to do is to get my hands on the bit patterns of 1.0f, >> -1.0f and x. Do I really have to copy the memory to do that? >> That seems like overkill. > > You don't have to copy the memory, you can simply read the bit > patterns > char by char, if you prefer. Any other kind of access will produce > wrong > assembly code on compilers with "strong" optimizers. > >> Can't I just form pointers to the float constants, cast the pointers >> to int pointers, and dereference them? > > No you can't. See paragraph 3.10/15 of the C++ standard. > > Best regards, > > Guillaume ... and of course this whole masking approach wouldn't work for an architecture where the sign of a floating point number was indicated by setting the sign bit such that the parity of all the bits in the number was odd for positive and even for negative! That is not to say that the bit test via mask is not potentially useful, just that one should be aware of its limitations. -- Martin Bonner Martin.Bonner(a)Pitechnology.com Pi Technology, Milton Hall, Ely Road, Milton, Cambridge, CB4 6WZ, ENGLAND Tel: +44 (0)1223 203894

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a cross-platform way to make temporary files?
by jmzorko＠mac.com 04 Aug '06

04 Aug '06

Hello, all ... Does boost provide an abstraction for creating temporary files (::GetTempFileName() on Win32, POSIX tmpfile / tmpname)? Regards, John Falling You - exploring the beauty of voice and sound http://www.fallingyou.com

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Portable signbit macro/function?
by Paul A Bristow 03 Aug '06

03 Aug '06

Does anyone have a ***portable*** version of macro signbit (C99) or can we combine versions that work on each compiler/hardware/endian... or an equivalent C++ function, perhaps called is_negative? (This would just test the signbit for the type(s)). There are several places where this would be useful in dealing properly with NaNs and zero and infinity etc. Thanks Paul PS Must be Boost license of course. --- Paul A Bristow Prizet Farmhouse, Kendal, Cumbria UK LA8 8AB +44 1539561830 & SMS, Mobile +44 7714 330204 & SMS pbristow(a)hetp.u-net.com

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[filesystem] create directory with wrong permissions
by Stephan Menzel 03 Aug '06

03 Aug '06

Hi there, when I am creating a directory with boost::filesystem::create_directory() the dir will be created, but the set permissions will not include 'executable' rights. Hance the application is not allowed to traverse into the dir it just created. System is Debian. With normal Unix functions all works well, so I think it must be another reason. Is there anything specific I have to do to ensure "drwx-r--r--" will be set? Greetings... Stephan

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Boost regression notification (2006-08-03 [RC_1_34_0])
by Douglas Gregor 03 Aug '06

03 Aug '06

Boost Regression test failures Report time: 2006-08-02T06:38:31Z This report lists all regression test failures on release platforms. Detailed report: http://engineering.meta-comm.com/boost-regression/CVS-RC_1_34_0/developer/i… 268 failures in 24 libraries algorithm/string (1) concept_check (1) filesystem (4) graph (5) io (1) iostreams (10) mpl (6) numeric/conversion (4) numeric/interval (1) numeric/ublas (7) parameter (22) program_options (9) python (85) random (1) rational (4) regex (1) serialization (25) signals (16) spirit (1) test (2) tr1 (51) typeof (9) utility (1) xpressive (1) |algorithm/string| regex: borland-5_6_4 |concept_check| class_concept_check_test: vc-7_1-stlport |filesystem| mbcopy: sun-5.8 operations_test: vc-7_1-stlport operations_test_dll: vc-7_1-stlport wide_test: sun-5.8 |graph| adjacency_matrix_test: vc-7_0 csr_graph_test: sun-5.8 graphviz_test: msvc-8.0 msvc-8.0 vc-7_1-stlport |io| ios_state_unit_test: gcc-4.1.0_linux_x86_64 |iostreams| bzip2_test: msvc-7.1 msvc-8.0 compose_test: borland-5_6_4 example_test: vc-6_5-stlport filtering_stream_test: vc-7_1-stlport finite_state_filter_test: cw-9.4 gzip_test: msvc-7.1 msvc-8.0 zlib_test: msvc-7.1 msvc-8.0 |mpl| multiset: gcc-4.0.3_linux gcc-4.1.0_linux gcc-4.1.0_linux_x86_64 gcc-4.1.1_sunos_i86pc gcc-4_0_3_tru64 vector_c: sun-5.8 |numeric/conversion| converter_test: borland-5_8_2 traits_test: borland-5_8_2 udt_example_0: borland-5_8_2 udt_support_test: borland-5_8_2 |numeric/interval| test_float: vc-7_1-stlport |numeric/ublas| concepts: vc-7_1-stlport vc-7_1-stlport test1: vc-7_1-stlport test2: vc-7_1-stlport test4: vc-7_1-stlport test5: vc-7_1-stlport vc-7_1-stlport |parameter| basics: borland-5_6_4 borland-5_8_2 duplicates: borland-5_6_4 borland-5_8_2 maybe: vc-6_5 vc-6_5-stlport vc-7_0 preprocessor: borland-5_6_4 borland-5_8_2 sun-5.8 vc-6_5 vc-6_5-stlport python-parameter-test: vc-6_5 vc-6_5-stlport vc-7_0 sfinae: borland-5_8_2 vc-6_5-stlport singular: borland-5_6_4 borland-5_8_2 unnamed_fail: vc-6_5 vc-6_5-stlport vc-7_0 |program_options| cmdline_test_dll: cw-9.4 options_description_test_dll: cw-9.4 parsers_test_dll: cw-9.4 positional_options_test_dll: cw-9.4 unicode_test_dll: borland-5_8_2 cw-9.4 variable_map_test_dll: borland-5_8_2 cw-9.4 winmain_dll: cw-9.4 |python| andreas_beyer: sun-5.8 args: sun-5.8 auto_ptr: sun-5.8 back_reference: sun-5.8 bases: gcc-3_4_4_tru64 gcc-4_0_3_tru64 sun-5.8 ben_scott1: sun-5.8 bienstman1: sun-5.8 bienstman2: sun-5.8 bienstman3: sun-5.8 borrowed: sun-5.8 callbacks: sun-5.8 const_argument: sun-5.8 crossmod_exception: sun-5.8 data_members: sun-5.8 defaults: sun-5.8 dict: sun-5.8 docstring: sun-5.8 enum: sun-5.8 exception_translator: sun-5.8 exec: cw-9.4 darwin-4.0.1 gcc-3_4_4_tru64 gcc-4_0_3_tru64 msvc-8.0 qcc-3.3.5_cpp qcc-3.3.5_cpp qcc-3.3.5_gpp qcc-3.3.5_gpp sun-5.8 extract: sun-5.8 implicit: sun-5.8 indirect_traits_test: sun-5.8 injected: sun-5.8 iterator: sun-5.8 keywords: sun-5.8 list: sun-5.8 long: sun-5.8 minimal: sun-5.8 multi_arg_constructor: sun-5.8 nested: sun-5.8 numpy: sun-5.8 object: sun-5.8 object_manager: sun-5.8 opaque: sun-5.8 operators: sun-5.8 pearu1: sun-5.8 pickle1: sun-5.8 pickle2: sun-5.8 pickle3: sun-5.8 pickle4: sun-5.8 pointee: gcc-3_4_4_tru64 gcc-4_0_3_tru64 sun-5.8 pointer_type_id_test: gcc-3_4_4_tru64 gcc-4_0_3_tru64 sun-5.8 pointer_vector: sun-5.8 polymorphism: sun-5.8 polymorphism2: sun-5.8 polymorphism2_auto_ptr: sun-5.8 properties: sun-5.8 raw_ctor: sun-5.8 return_arg: sun-5.8 select_arg_to_python_test: sun-5.8 select_from_python_test: darwin-4.0.1 sun-5.8 select_holder: sun-5.8 shared_ptr: sun-5.8 slice: sun-5.8 staticmethod: sun-5.8 stl_iterator: sun-5.8 str: sun-5.8 string_literal: sun-5.8 test_pointer_adoption: sun-5.8 try: sun-5.8 tuple: sun-5.8 upcast: gcc-3_4_4_tru64 gcc-4_0_3_tru64 sun-5.8 vector_indexing_suite: sun-5.8 virtual_functions: sun-5.8 voidptr: sun-5.8 wrapper_held_type: sun-5.8 |random| random_test: intel-linux-9.0 |rational| rational_test: borland-5_6_4 vc-6_5 vc-6_5-stlport vc-7_0 |regex| regex_regress_threaded: gcc-4_0_3_tru64 |serialization| test_class_info_load_text_warchive: vc-6_5 test_non_default_ctor2_text_archive: qcc-3.3.5_cpp qcc-3.3.5_cpp qcc-3.3.5_cpp test_non_default_ctor2_text_archive_dll: qcc-3.3.5_cpp qcc-3.3.5_cpp qcc-3.3.5_cpp test_non_default_ctor2_text_warchive: qcc-3.3.5_cpp qcc-3.3.5_cpp qcc-3.3.5_cpp test_non_default_ctor2_text_warchive_dll: qcc-3.3.5_cpp qcc-3.3.5_cpp qcc-3.3.5_cpp test_reset_object_address: vc-7_0 test_reset_object_address_dll: vc-7_0 test_set_text_archive_dll: msvc-8.0 test_simple_class_binary_archive_dll: vc-6_5 test_simple_class_text_archive_dll: vc-6_5 test_simple_class_text_warchive_dll: vc-6_5 test_simple_class_xml_archive_dll: vc-6_5 test_simple_class_xml_warchive_dll: vc-6_5 test_variant_xml_archive: borland-5_8_2 test_variant_xml_archive_dll: borland-5_8_2 test_variant_xml_warchive: borland-5_8_2 test_variant_xml_warchive_dll: borland-5_8_2 |signals| dead_slot_test: gcc-3.3.6 gcc-3.3.6_linux qcc-3.3.5_cpp qcc-3.3.5_cpp qcc-3.3.5_cpp qcc-3.3.5_gpp qcc-3.3.5_gpp qcc-3.3.5_gpp trackable_test: gcc-3.3.6 gcc-3.3.6_linux qcc-3.3.5_cpp qcc-3.3.5_cpp qcc-3.3.5_cpp qcc-3.3.5_gpp qcc-3.3.5_gpp qcc-3.3.5_gpp |spirit| mix_and_match_trees: sun-5.8 |test| parameterized_test_test: vc-6_5 vc-6_5-stlport |tr1| run_random: sun-5.8 std_run_complex_overloads: sun-5.8 std_run_random: sun-5.8 std_test_bind: sun-5.8 std_test_complex: sun-5.8 std_test_function: sun-5.8 std_test_hash: sun-5.8 std_test_mem_fn: sun-5.8 std_test_random: sun-5.8 std_test_reference_wrapper: sun-5.8 std_test_reference_wrapper_tricky: gcc-3.2.3_linux gcc-3.3.6_linux gcc-3.4.5_linux gcc-3.4.5_linux_x86_64 gcc-4.0.3_linux gcc-4.1.0_linux_x86_64 intel-linux-9.0 mingw-3_4_2 msvc-7.1 msvc-8.0 qcc-3.3.5_cpp qcc-3.3.5_cpp qcc-3.3.5_gpp qcc-3.3.5_gpp vc-7_1-stlport std_test_result_of: sun-5.8 std_test_shared_ptr: sun-5.8 std_test_tuple: sun-5.8 std_test_tuple_tricky: sun-5.8 std_test_type_traits: sun-5.8 test_boost: vc-7_1-stlport test_hash: vc-7_1-stlport test_random: sun-5.8 vc-7_1-stlport test_reference_wrapper_tricky: gcc-3.2.3_linux gcc-3.3.6_linux gcc-3.4.5_linux gcc-3.4.5_linux_x86_64 gcc-4.0.3_linux gcc-4.1.0_linux_x86_64 intel-linux-9.0 mingw-3_4_2 msvc-7.1 msvc-8.0 qcc-3.3.5_cpp qcc-3.3.5_cpp qcc-3.3.5_gpp qcc-3.3.5_gpp test_regex: vc-7_1-stlport test_type_traits: sun-5.8 tr1_tky_function_type_test: sun-5.8 |typeof| function_binding_emulation: sun-5.8 function_binding_native: vc-6_5 vc-6_5-stlport vc-7_0 nested_typedef_emulation: cw-9.4 odr_no_uns: vc-6_5 vc-6_5-stlport vc-7_0 template_tpl_emulation: sun-5.8 |utility| operators_test: gcc-3.4.5_linux_x86_64 |xpressive| test7: msvc-8.0

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[iostreams] patch for close(sink, in|out)
by Takeshi Mouri 03 Aug '06

03 Aug '06

Hello, I noticed that there is a problem in treating the parameter "which" on iostreams::close(). So, the following code doesn't output anything to standard output. #include <boost/iostreams/categories.hpp> #include <boost/iostreams/close.hpp> #include <iostream> namespace io = boost::iostreams; class test_sink { public: typedef char char_type; struct category : io::output, io::device_tag, io::closable_tag {}; std::streamsize write(const char*, std::streamsize n) { return n; } void close() { std::cout << "called test_sink::close()" << std::endl; } }; int main() { test_sink sink; // doesn't call test_sink::close() io::close(sink, BOOST_IOS::in|BOOST_IOS::out); } OTH, some device adapters in Boost.Iostreams perform such function call for closing the external device. Such the adapters never close the external device. The attachment is a patch for this problem. Regards, Takeshi Mouri

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Re: [boost] Portable signbit macro/function?
by Martin Bonner 03 Aug '06

03 Aug '06

----Original Message---- From: boost-bounces(a)lists.boost.org [mailto:boost-bounces@lists.boost.org] On Behalf Of Johan Råde Sent: 03 August 2006 12:38 To: boost(a)lists.boost.org Subject: Re: [boost] Portable signbit macro/function? > John Maddock wrote: > >> And the endianness of the float's if you're doing bit testing. But >> of course if there is a macro already it's easy enough to convert it >> into a function. > > The following function does bit testing, without advance knowledge of > which bit is the sign bit. The function figures out on its own, at > compile time, which bit is the sign bit. Hence you do not have to > worry > about IEEE 754 and endianness. The only thing that is required is that > sizeof(float) == sizeof(int). It also requires that the sign bit of the float is in the same place as the sign bit of the int ... which it is for most usual implementations of IEEE 754 (although I'm not sure if the standard actually refers to byte ordering issues), but I don't think it is true for Vax floating point formats. > > bool signbit(float x) > { > const float one = 1; > const float neg_one = -1; > const int sign_mask = reinterpret_cast<const int&>(one) > ^ reinterpret_cast<const int&>(neg_one); > return reinterpret_cast<int&>(x) & sign_mask; > } > > I have tested it on VC++ 7.1 with signed zeroes, signed infinities and > signed NaNs, and plain signed numbers. Can I suggest that you study the tenth commandment for C programmers at http://www.lysator.liu.se/c/ten-commandments.html. C++ avoids the need for some of those commandments, but that one has stood the test of time with undiminished force. -- Martin Bonner Martin.Bonner(a)Pitechnology.com Pi Technology, Milton Hall, Ely Road, Milton, Cambridge, CB4 6WZ, ENGLAND Tel: +44 (0)1223 203894

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[ublas] Serious bug in mapped_vector_of_mapped_vector
by Matthias Troyer 03 Aug '06

03 Aug '06

There is a serious bug in the mapped_vector_of_mapped_vector spare matrix type. Rows containing only zero elements are not treated correctly in prod(). The following code should give a vector that contains only 1 in the last element. Instead prod() gives a vector containing 1 in each element. In debug mode this bug is found by the checks: Check failed in file boost/boost/numeric/ublas/detail/ vector_assign.hpp at line 371: detail::expression_type_check (v, cv) Aborted The bug appears in Boost 1.33 as well as in the CVS version Best regards Matthias #include <boost/numeric/ublas/matrix_sparse.hpp> #include <boost/numeric/ublas/vector.hpp> int main() { boost::numeric::ublas::mapped_vector_of_mapped_vector<double> m (64,64); boost::numeric::ublas::vector<double> v(64); boost::numeric::ublas::vector<double> w(64); v[63] = 1.; m(63,63) = 1.; w = boost::numeric::ublas::prod(m,v); }

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[Boost-bugs] [ boost-Bugs-1533595 ] serializing empty vectors triggers STL assertion failure (VC
by SourceForge.net 03 Aug '06

03 Aug '06

Bugs item #1533595, was opened at 2006-08-03 04:39 Message generated for change (Tracker Item Submitted) made by Item Submitter You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=107586&aid=1533595&group_… Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: serialization Group: None Status: Open Resolution: None Priority: 5 Submitted By: Thomas Pintaric (pintaric) Assigned to: Robert Ramey (ramey) Summary: serializing empty vectors triggers STL assertion failure (VC Initial Comment: Serializing empty vectors triggers an STL assertion failure (VC++ 8.0). Test case: ========== typedef std::vector<int> vec_t; vec_t v; // empty vector { std::ofstream ofs("test.dat"); boost::archive::binary_oarchive oa(ofs); oa << v; // triggers runtime assertion } The assertion is caused by line 31 in serialization/detail/get_data.hpp (note that vector v is empty): [0031] return &(v[0]); Proposed fix: ============= Index: oarchive.hpp =================================================================== RCS file: /cvsroot/boost/boost/boost/archive/array/oarchive.hpp,v retrieving revision 1.3 diff -r1.3 oarchive.hpp 73c73 < * this->This() << serialization::make_array(serialization::detail::get_data(t),t.size()); --- > if(count) * this->This() << serialization::make_array(serialization::detail::get_data(t),t.size()); Index: iarchive.hpp =================================================================== RCS file: /cvsroot/boost/boost/boost/archive/array/iarchive.hpp,v retrieving revision 1.3 diff -r1.3 iarchive.hpp 77c77 < * this->This() >> serialization::make_array(serialization::detail::get_data(t),t.size()); --- > if(count) * this->This() >> serialization::make_array(serialization::detail::get_data(t),t.size()); ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=107586&aid=1533595&group_… ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys -- and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Boost-bugs mailing list Boost-bugs(a)lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/boost-bugs

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