CC1310: The problem of task stack size

Hi,

I have a problem .I am developing rfWsnNode,cc1310,simplelink cc1310 1.50.

The default task stack size of Nodetask is 1024.but i define a char array with 1024 elements, so i change the stack size to 2048,after changing, i find the code works abnormal,.

I search the map,

50 127 bytes of readonly code memory
13 948 bytes of readonly data memory
11 998 bytes of readwrite data memory,

so,what's the problem of that?

Thanks!