terminate called after throwing an instance of 'std::bad_alloc'

[lzqustc]

2021-08-16 06:31:33.621 [ 4] E AplClientBridge:AplClientRenderer::executeCommands
2021-08-16 06:31:33.621 [ 4] E AplClientBridge:executeCommands::create document
2021-08-16 06:31:33.621 [ 4] E AplClientBridge:executeCommands::Parse
2021-08-16 06:31:33.621 [ 4] E AplClientBridge:executeCommands::FindMember(commands)
2021-08-16 06:31:33.621 [ 4] E AplClientBridge:executeCommands::create apl::Object
2021-08-16 06:31:33.621 [ 4] E AplClientBridge:executeCommands::m_Root->executeCommands
2021-08-16 06:31:33.626 [ 4] E AplClientBridge:AplCoreEngine::delayaction.cpp:checkCommand: DelayAction::checkCommand(), mCommand->execute
2021-08-16 06:31:33.632 [ 4] E AplClientBridge:AplCoreEngine::corecommand.cpp:validate : CoreCommand::validate()
2021-08-16 06:31:33.632 [ 4] E AplClientBridge:AplCoreEngine::speakitemcommand.cpp:propDefSet : SpeakItemCommand::propDefSet()
2021-08-16 06:31:33.650 [ 4] E AplClientBridge:AplCoreEngine::corecommand.cpp:propDefSet : CoreCommand::propDefSet, buddyinfo=
Node 0, zone DMA 19 20 20 10 7 4 4 5 5 5 63
Node 0, zone HighMem 7 1 1 1 1 3 1 2 0 3 112

2021-08-16 06:31:33.670 [ 4] E AplClientBridge:AplCoreEngine::corecommand.cpp:propDefSet : CoreCommand::propDefSet, free=
total used free shared buff/cache available
Mem: 1338336 278312 745172 15664 314852 976416
Swap: 358396 0 358396

terminate called after throwing an instance of 'std::bad_alloc'
what(): std::bad_alloc

APL [1.6.1]
using AVSDeviceSDk 1.24 + SmartScreenSDK 2.7, test the " Alexa, tell me a joke"
armv7, arm linux, gcc version 5.5.0 (Linaro GCC 5.5-2017.10)

I think since the memory is enough (by checking "free" or "cat /proc/buddyinfo"), it shouldn't throw the bad_alloc.
The break point is the function propDefSet() of all xxxcommands.cpp

but if I move the function propDefSet() from xxxcommands.cpp to xxxcommands.h, then the 'bad_alloc' issue is gone.
And I notice that in the version APL[1.3.2], the propDefSet() are defined and implemented in all head files.

so my question is , why move propDefSet() from .h to .cpp? and why this change can lead to 'bad_alloc' crash issue?