Issue JTAG debugging U-Boot

Hi

I am trying to debug the NAND driver (U-boot 2016.09) and ran into the following issue: After changing target CC options to -Og -g in the Makefile and building U-Boot the debugger doesn’t show the value for the nand_chip structure and tells me that is has been optimized out. Also, I can view all values of the MTD structure, but the pointer to the chip structured shows the same. Marking the chip structure as volatile does not change the behavior. So, why is just this structure optimized out and how can I fix this?

BTW: I do not have such problems debugging U-Boot 2013.