It's likely heap corruption, you could inspect you code's use of pointers and ensure nothing is witting out of bounds or
 writing to a freed memory.

If it's not reproducible with debug, you can try more light weight instrumentation, perhaps creating malloc/free/calloc 
wrapper.

-Joel

________________________________________
From: atish bhowmick [community-noreply@qnx.com]
Sent: Wednesday, January 07, 2015 12:27 PM
To: technology-networking
Subject: malloc failure for std::string

I am getting a random crash with the following error :
Malloc Check Failed: :/builds/660_SDP/svn/lib/c/alloc/band.c:492
I am using Momentics 5.0 & Qnx 6.6 .

from the core dump (given below ) I can see that malloc is failing is for std::string objects & operations which I am using in my code . I have run the exe in debug mode with memory analysis tooladded from Momentics IDE. I also enabled all the memory error check options in memory analysis tool tab. But in all these debug runs no crash occurs in the scenario .Also the memory analysis view doesnt show any memory problems with the exe after several runs.

However when i execute the same code in non debug mode or debug mode without memory analysis tool , I get the same memory allocation crash . It occurs randomly at different places in the code where I am doing std::string operations for which memory allocations are required . Below is a call stack :
                        SignalKill() at 0xb034cf5d
                        raise() at 0xb0336348
                        __malloc_panic_str() at 0xb033020a
                        __malloc_panic() at 0xb03302ed
                        _band_get_aligned() at 0xb032ea19
                        _band_get() at 0xb032ebeb
                        __malloc_lock.constprop.2() at 0xb0332c00
                        malloc() at 0xb033289b
                        operator new() at 0xb825f7ca
                        std::_Allocate<char>() at xmemory0:18 0x8052df4
                        std::allocator<char>::allocate() at xmemory0:741 0x8052ca9
                        std::_Wrap_alloc<std::allocator<char> >::allocate() at xmemory0:1,067 0x80529ae
                        std::string::_Copy() at xstring:2,310 0x8051dde
                        std::string::_Grow() at xstring:2,341 0x80515a1
                        std::string::append() at xstring:1,171 0x8050de7
                        std::string::append() at xstring:1,182 0x805013b
                        std::string::operator+=() at xstring:1,124 0x8060d16
                        QNXCommonUtils::readLineBuffered() at QNXCommonUtils.cpp:158 0x806ab4d
                        SystemConfig::readIniFileInMem() at SystemConfig.cpp:461 0x80562cb
                        SystemConfig::mergeNVPData() at SystemConfig.cpp:2,176 0x805d86e
                        SystemConfig::updateIniFile() at SystemConfig.cpp:938 0x8057e73
                        SystemConfig::UpdateAllIni() at SystemConfig.cpp:866 0x8057b6e
                        CQNXUpgradeManager::processIPSPolicyUpdate() at CQNXUpgradeManager.cpp:501 0x807ae6f
                        CQNXUpgradeManager::applyThePackage() at CQNXUpgradeManager.cpp:896 0x807cc73
                        CQNXUpgradeManager::run() at CQNXUpgradeManager.cpp:1,377 0x807f258
                        Thread<CQNXUpgradeManager>::ThreadFunc() at Thread.h:59 0x8051330

Any pointers wud be very helpful to find the root cause of malloc failure .



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