Hi, On 12/02/16 09:19, Umesh Kalappa wrote:
Hi Guys ,we do have a issue with below code ,When we enabled the pie (-fpie/pie) option i.e main.c extern int *my_ptr ; int main() { return *my_ptr; } foo.s .syntax unified .cpu cortex-m0 .fpu softvfp .thumb .global my_ptr .global my_var .data .align 2 .type my_ptr, %object .size my_ptr, 4 my_ptr: .word my_var //where my_var is the linker variable custom.ld (linker script) /* Set stack top to end of RAM, and stack limit move down by 190 * size of stack_dummy section */ 191 my_var = 20; 192 __StackTop = ORIGIN(RAM) + LENGTH(RAM); 193 __StackLimit = __StackTop - SIZEOF(.stack_dummy); 194 PROVIDE(__stack = __StackTop); command used 3 arm-none-eabi-gcc -c -fPIC main.c -mthumb -mcpu=cortex-m0 4 5 arm-none-eabi-gcc -c -fPIC foo.S -mthumb -mcpu=cortex-m0 6 arm-none-eabi-gcc -c -fPIC /home/egoumal/Downloads/gcc-arm-none-eabi-5_2-2015q4/share/gcc-arm-none-eabi/samples/startup/startu p_ARMCM0.S -mthumb -mcpu=cortex-m0 -D__STARTUP_CLEAR_BSS -D__START=main 7 8 arm-none-eabi-ld -pie main.o foo.o startup_ARMCM0.o -L. -L/home/egoumal/Downloads/gcc-arm-none-eabi-5_2-2015q4/share/gcc-ar m-none-eabi/samples/ldscripts -T nokeep.ld -Map=test.map -o test we expect my_ptr value to be 20 ,but we do see the value 0 and without pie option ,the my_ptr has the value 20 . do we missing something here or value 0 expected (which is incorrect)
note that gcc-bugs is the list where the automatic bug tracker sends all the emails logging almost all activity, so your email would be lost there... Please file a bug report in bugzilla according to https://gcc.gnu.org/bugs/ Thanks, Kyrill
Thank you and appreciate any lights on this ~Umesh
