ON-Chip Memory is too small for the source code

Option 1

If you want to move a whole memory section to ddr2 or to any another memory, select it in the BSP properties.

e.g. : stack in onchip memory, code in ddr2, data in ddr2, ...

Option 2

If you want to move a single function to a specific memory, add

__attribute__ ((section (".my_memory")))

after the function declaration, where 'my_memory' is the name you assigned to your memory in sopc builder or Qsys.

e.g. int function_in_ddr2(int param) __attribute__ ((section (".ddr2_ext_mem")));

Option 3

Use a custom linker scripts and map whatever you want wherever you need.