Here's a little GDB trick, if you want to debug your program using assembly output.
From a GDB session, type:
display /i $pc break main
The first line will tell GCC to output the assembly code. The second one will create a breakpoint on the main function. You can of course choose another symbol for the breakpoint.
Once done, you can run your program:
In our example, to code will stop at the main function, showing the assembly code:
Breakpoint 1, main () at test.c:3 3 return 0; 1: x/i $pc 0x100000f3c : mov $0x0,%eax
You can then step to each assembly instruction with the