Application crashes after .Net runtime upgrade to .Net4.6

Recently, our application(32 bit process) will crash after running several hours due to CLR internal error, like below:

Faulting application name: XXX.exe, version: 7.20.0.1230, time stamp: 0x5682c035

We think it shall related to .Net4.6 as it works fine in .Net4.5 and before version.
And we find below GC configuration:

<runtime>

can improve our application stability obviously -- Application can run more than one day, though it still will crash eventually!!! 

The dump file call stack is like below:     

>clr.dll!SVR::memcopy(unsigned char *,unsigned char *,unsigned int)Unknown
clr.dll!SVR::gc_heap::compact_plug(unsigned char *,unsigned int,int,struct SVR::gc_heap::compact_args *)Unknown
clr.dll!SVR::gc_heap::compact_in_brick(unsigned char *,struct SVR::gc_heap::compact_args *)Unknown
clr.dll!SVR::gc_heap::compact_in_brick(unsigned char *,struct SVR::gc_heap::compact_args *)Unknown
clr.dll!SVR::gc_heap::compact_phase(int,unsigned char *,int)Unknown
clr.dll!SVR::gc_heap::plan_phase(int)Unknown
clr.dll!SVR::gc_heap::gc1(void)Unknown
clr.dll!SVR::gc_heap::garbage_collect(int)Unknown
clr.dll!SVR::gc_heap::gc_thread_function(void)Unknown
clr.dll!SVR::gc_heap::gc_thread_stub(void *)Unknown
kernel32.dll!@BaseThreadInitThunk@12()Unknown
ntdll.dll!___RtlUserThreadStart@8()Unknown
ntdll.dll!__RtlUserThreadStart@8()Unknown

Any clue?