{ ZLib doesn't allocate its buffer. This is no bug according to the FAQ. Memcheck:Cond fun:longest_match fun:deflate_slow fun:deflate } { Not sure why this happens. Memcheck:Leak fun:calloc fun:_dl_allocate_tls fun:pthread_create@@GLIBC_2.1 fun:_ZN5boost6thread12start_threadEv } { Memcheck:Leak fun:malloc fun:__cxa_get_globals fun:__cxa_allocate_exception fun:_ZN5boost14copy_exceptionINS_16exception_detail10bad_alloc_EEENS_10shared_ptrIKNS1_10clone_baseEEERKT_ fun:_ZN5boost16exception_detail13get_bad_allocILi42EEENS_10shared_ptrIKNS0_10clone_baseEEEv fun:_Z41__static_initialization_and_destruction_0ii fun:_GLOBAL__I__ZN12_GLOBAL__N_12_1E fun:_ZN16ImageLoaderMachO18doModInitFunctionsERKN11ImageLoader11LinkContextE fun:_ZN11ImageLoader23recursiveInitializationERKNS_11LinkContextEj fun:_ZN11ImageLoader15runInitializersERKNS_11LinkContextE fun:_ZN4dyld24initializeMainExecutableEv fun:_ZN4dyld5_mainEPK12macho_headermiPPKcS5_S5_ } { Memcheck:Param socketcall.sendto(msg) fun:sendto fun:getaddrinfo } { Memcheck:Cond fun:BN_bin2bn } { Memcheck:Cond fun:BN_num_bits_word } { Memcheck:Cond fun:BN_num_bits } { Memcheck:Value4 fun:BN_mod_exp_mont_consttime fun:BN_mod_exp_mont } { Memcheck:Value4 fun:BN_num_bits_word fun:BN_mod_exp_mont_consttime fun:BN_mod_exp_mont } { Memcheck:Value8 fun:BN_num_bits } { Memcheck:Value8 fun:BN_mod_exp_mont_consttime } { Memcheck:Cond fun:*mersenne_twister* } { Memcheck:Leak fun:malloc fun:__cxa_get_globals } { ZLib Memcheck:Cond fun:deflateEnd fun:deflateSetDictionary fun:deflate } { Uninitialized value from boost uuid Memcheck:Value8 fun:_ZSt13__int_to_charIcmEiPT_T0_PKS0_St13_Ios_Fmtflagsb fun:_ZNKSt7num_putIcSt19ostreambuf_iteratorIcSt11char_traitsIcEEE13_M_insert_intImEES3_S3_RSt8ios_basecT_ fun:_ZNKSt7num_putIcSt19ostreambuf_iteratorIcSt11char_traitsIcEEE6do_putES3_RSt8ios_basecm fun:_ZNSo9_M_insertImEERSoT_ fun:_ZN5boost5uuidslsIcSt11char_traitsIcEEERSt13basic_ostreamIT_T0_ES8_RKNS0_4uuidE fun:_ZN5Swift13ClientSession13handleElementEN5boost10shared_ptrINS_7ElementEEE fun:_ZNK5boost4_mfi3mf1IvN5Swift13ClientSessionENS_10shared_ptrINS2_7ElementEEEE4callINS4_IS3_EES6_EEvRT_PKvRT0_ fun:_ZNK5boost4_mfi3mf1IvN5Swift13ClientSessionENS_10shared_ptrINS2_7ElementEEEEclINS4_IS3_EEEEvRT_S6_ fun:_ZN5boost3_bi5list2INS0_5valueINS_10shared_ptrIN5Swift13ClientSessionEEEEENS_3argILi1EEEEclINS_4_mfi3mf1IvS5_NS3_INS4_7ElementEEEEENS0_5list1IRSF_EEEEvNS0_4typeIvEERT_RT0_i fun:_ZN5boost3_bi6bind_tIvNS_4_mfi3mf1IvN5Swift13ClientSessionENS_10shared_ptrINS4_7ElementEEEEENS0_5list2INS0_5valueINS6_IS5_EEEENS_3argILi1EEEEEEclIS8_EEvRT_ fun:_ZN5boost6detail8function26void_function_obj_invoker1INS_3_bi6bind_tIvNS_4_mfi3mf1IvN5Swift13ClientSessionENS_10shared_ptrINS7_7ElementEEEEENS3_5list2INS3_5valueINS9_IS8_EEEENS_3argILi1EEEEEEEvSB_E6invokeERNS1_15function_bufferESB_ fun:_ZNK5boost9function1IvNS_10shared_ptrIN5Swift7ElementEEEEclES4_ } { Uninitialized value from boost uuid Memcheck:Cond fun:_ZSt13__int_to_charIcmEiPT_T0_PKS0_St13_Ios_Fmtflagsb fun:_ZNKSt7num_putIcSt19ostreambuf_iteratorIcSt11char_traitsIcEEE13_M_insert_intImEES3_S3_RSt8ios_basecT_ fun:_ZNKSt7num_putIcSt19ostreambuf_iteratorIcSt11char_traitsIcEEE6do_putES3_RSt8ios_basecm fun:_ZNSo9_M_insertImEERSoT_ fun:_ZN5boost5uuidslsIcSt11char_traitsIcEEERSt13basic_ostreamIT_T0_ES8_RKNS0_4uuidE fun:_ZN5Swift13ClientSession13handleElementEN5boost10shared_ptrINS_7ElementEEE fun:_ZNK5boost4_mfi3mf1IvN5Swift13ClientSessionENS_10shared_ptrINS2_7ElementEEEE4callINS4_IS3_EES6_EEvRT_PKvRT0_ fun:_ZNK5boost4_mfi3mf1IvN5Swift13ClientSessionENS_10shared_ptrINS2_7ElementEEEEclINS4_IS3_EEEEvRT_S6_ fun:_ZN5boost3_bi5list2INS0_5valueINS_10shared_ptrIN5Swift13ClientSessionEEEEENS_3argILi1EEEEclINS_4_mfi3mf1IvS5_NS3_INS4_7ElementEEEEENS0_5list1IRSF_EEEEvNS0_4typeIvEERT_RT0_i fun:_ZN5boost3_bi6bind_tIvNS_4_mfi3mf1IvN5Swift13ClientSessionENS_10shared_ptrINS4_7ElementEEEEENS0_5list2INS0_5valueINS6_IS5_EEEENS_3argILi1EEEEEEclIS8_EEvRT_ fun:_ZN5boost6detail8function26void_function_obj_invoker1INS_3_bi6bind_tIvNS_4_mfi3mf1IvN5Swift13ClientSessionENS_10shared_ptrINS7_7ElementEEEEENS3_5list2INS3_5valueINS9_IS8_EEEENS_3argILi1EEEEEEEvSB_E6invokeERNS1_15function_bufferESB_ fun:_ZNK5boost9function1IvNS_10shared_ptrIN5Swift7ElementEEEEclES4_ } { dateFromString warning Memcheck:Cond fun:strftime_l fun:_ZNKSt11__timepunctIcE6_M_putEPcmPKcPK2tm fun:_ZNKSt8time_putIcSt19ostreambuf_iteratorIcSt11char_traitsIcEEE6do_putES3_RSt8ios_basecPK2tmcc fun:_ZNKSt8time_putIcSt19ostreambuf_iteratorIcSt11char_traitsIcEEE3putES3_RSt8ios_basecPK2tmPKcSB_ fun:_ZN5boost9date_time20gather_month_stringsIcEESt6vectorISbIT_St11char_traitsIS3_ESaIS3_EESaIS7_EERKSt6localeb fun:_ZN5boost9date_time18format_date_parserINS_9gregorian4dateEcEC1ERKSsRKSt6locale fun:_ZN5boost9date_time16date_input_facetINS_9gregorian4dateEcSt19istreambuf_iteratorIcSt11char_traitsIcEEEC2ERKSsm fun:_ZN5boost9date_time16time_input_facetINS_10posix_time5ptimeEcSt19istreambuf_iteratorIcSt11char_traitsIcEEEC1ERKSsm fun:_ZN5Swift11DelayParser14dateFromStringERKNS_6StringE