On Wednesday, March 11, 2015 07:18 PM, Ben Pope wrote:
On Wednesday, March 11, 2015 05:43 PM, Andrey Semashev wrote:
On Wed, Mar 11, 2015 at 12:32 PM, Fletcher, John P <j.p.fletcher@aston.ac.uk> wrote:
There is a test set on develop called BenPope x86_64 Ubuntu - phoenix - adapt_function / clang-linux-3.6~msan~c14_libc++
This runs this command line for example on the Phoenix test "adapt_function":
"clang++-3.6" -c -x c++ -std=c++1y -stdlib=libc++ -fsanitize=memory -O0 -fno-inline -Wall -fPIC -m64 -DBOOST_ALL_NO_LIB=1 -I".." -o "/home/ben/development/boost/test/build/develop/results/boost/bin.v2/libs/phoenix/test/adapt_function.test/clang-linux-3.6~msan~c14_libc++/debug/address-model-64/architecture-x86/debug-symbols-off/function/adapt_function.o" "../libs/phoenix/test/function/adapt_function.cpp"
There are numerous failures with this test set on Phoenix and I set out to find out why.
Most of the failures are like this:
SUMMARY: MemorySanitizer: use-of-uninitialized-value ??:0 std::__1::basic_ostream<char, std::__1::char_traits<char> >& std::__1::__put_character_sequence<char, std::__1::char_traits<char>
(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, char const*, unsigned long) Exiting
I think this is coming from the boost::report_errors function defined in boost/core/lightweight_test.hpp
I have put some temporary tests on to develop for Phoenix which contain only various calls to test the lightweight test. These are called aa_test0 to 3 so they will come at the top of the table. Unfortunately tests are not reporting at the moment so I don't have any results.
There are also failures on the testing of Boost Core with the same test set.
I thought I would report this without waiting for the results in the hope that it can be sorted out for the 1.58.0 release.
This looks like a string insertion operator implementation. I don't see how the string memory could be uninitialized since there are only literals used in report_errors(), as well as other functions, unless you use BOOST_ERROR with uninitialized buffer as the message string. I suspect a false positive. Does MSan report an error for this code sample:
#include <iostream>
int main() { std::cerr << "Hello, world!" << std::endl; return 0; }
Yes.
ben@yyls03:~/development/test$ ./a.out ==4752== WARNING: MemorySanitizer: use-of-uninitialized-value #0 0x7f0103b09f3f in std::__1::basic_ostream<char, std::__1::char_traits<char> >& std::__1::__put_character_sequence<char, std::__1::char_traits<char> >(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, char const*, unsigned long) (/home/ben/development/test/a.out+0x8bf3f) #1 0x7f0103b09602 in std::__1::basic_ostream<char, std::__1::char_traits<char> >& std::__1::operator<< <std::__1::char_traits<char> >(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, char const*) (/home/ben/development/test/a.out+0x8b602) #2 0x7f0103b094d6 in main (/home/ben/development/test/a.out+0x8b4d6) #3 0x7f0102462ec4 in __libc_start_main /build/buildd/eglibc-2.19/csu/libc-start.c:287 #4 0x7f0103ab4f7e in _start (/home/ben/development/test/a.out+0x36f7e)
SUMMARY: MemorySanitizer: use-of-uninitialized-value ??:0 std::__1::basic_ostream<char, std::__1::char_traits<char> >& std::__1::__put_character_sequence<char, std::__1::char_traits<char>
(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, char const*, unsigned long) Exiting
I've added it to the blacklist now, hopefully I have the correct incantation and significantly reduce the false positives.
Hmmm, flags aren't being passed correctly: <test-log library="core" revision="dd17b0" test-name="explicit_operator_bool_noexcept" test-type="run" test-program="libs/core/test/explicit_operator_bool_noexcept.cpp" target-directory="boost/bin.v2/libs/core/test/explicit_operator_bool_noexcept.test/clang-linux-3.6~msan~c14_libc++/debug/address-model-64/architecture-x86" toolset="clang-linux-3.6~msan~c14_libc++" show-run-output="false"> <compile result="succeed" timestamp="2015-03-12 14:33:21 UTC"> "clang++-3.6" -c -x c++ -std=c++1y -stdlib=libc++ -fsanitize=memory -O0 -g -fno-inline -Wall -g -fPIC -m64 -DBOOST_ALL_NO_LIB=1 -I".." -o "/home/ben/development/boost/test/build/results/boost/bin.v2/libs/core/test/explicit_operator_bool_noexcept.test/clang-linux-3.6~msan~c14_libc++/debug/address-model-64/architecture-x86/explicit_operator_bool_noexcept.o" "../libs/core/test/explicit_operator_bool_noexcept.cpp" </compile> <link result="succeed" timestamp="2015-03-12 14:33:21 UTC"> "clang++-3.6" -o "/home/ben/development/boost/test/build/results/boost/bin.v2/libs/core/test/explicit_operator_bool_noexcept.test/clang-linux-3.6~msan~c14_libc++/debug/address-model-64/architecture-x86/explicit_operator_bool_noexcept" -Wl,--start-group "/home/ben/development/boost/test/build/results/boost/bin.v2/libs/core/test/explicit_operator_bool_noexcept.test/clang-linux-3.6~msan~c14_libc++/debug/address-model-64/architecture-x86/explicit_operator_bool_noexcept.o" -Wl,-Bstatic -Wl,-Bdynamic -Wl,--end-group -g -fsanitize=memory -fsanitize-blacklist=/home/ben/sanitize-blacklist.txt -lc++ -lc++abi -m64 </link> <run result="fail" timestamp="2015-03-12 14:33:21 UTC"> ==24502== WARNING: MemorySanitizer: use-of-uninitialized-value #0 0x7fc24c95f9bf in std::__1::basic_ostream<char, std::__1::char_traits<char> >& std::__1::__put_character_sequence<char, std::__1::char_traits<char> >(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, char const*, unsigned long) /home/ben/development/llvm/3.6/install/release/bin/../include/c++/v1/ostream:752:13 #1 0x7fc24c95f082 in std::__1::basic_ostream<char, std::__1::char_traits<char> >& std::__1::operator<< <std::__1::char_traits<char> >(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, char const*) /home/ben/development/llvm/3.6/install/release/bin/../include/c++/v1/ostream:894:12 #2 0x7fc24c95eb31 in boost::report_errors() /home/ben/development/boost/test/build/boost_root/status/../boost/core/lightweight_test.hpp:133:11 #3 0x7fc24c95e952 in main /home/ben/development/boost/test/build/boost_root/status/../libs/core/test/explicit_operator_bool_noexcept.cpp:79:12 #4 0x7fc24afaaec4 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21ec4) #5 0x7fc24c90a3ee in _start (/home/ben/development/boost/test/build/results/boost/bin.v2/libs/core/test/explicit_operator_bool_noexcept.test/clang-linux-3.6~msan~c14_libc++/debug/address-model-64/architecture-x86/explicit_operator_bool_noexcept+0x363ee) SUMMARY: MemorySanitizer: use-of-uninitialized-value /home/ben/development/llvm/3.6/install/release/bin/../include/c++/v1/ostream:752 std::__1::basic_ostream<char, std::__1::char_traits<char> >& std::__1::__put_character_sequence<char, std::__1::char_traits<char> >(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, char const*, unsigned long) Exiting EXIT STATUS: 77 </run> </test-log> -fsanitize-blacklist needs passing at compile time, not link time. Ben