gdb cannot step into printf

Question

here is my sample program:

#include<stdio.h>

int main()
{

printf("hello good morning \n");
return 0;
}


gcc -Wall -g temp.c


/opt/langtools/bin/gdb a.out
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..
(gdb) b 6
Breakpoint 1 at 0x2b14: file temp.c, line 6.
(gdb) run
Starting program: /oo_dgfqausr/test/dfqwrk4/temp/a.out

Breakpoint 1, main () at temp.c:6
6       printf("hello good morning \n");
(gdb) step
hello good morning
7       return 0;
(gdb)

as soon as i try to step into the printf function.its exiting and returning to main. does this mean that the shred library in which the printf function is defined is not provided with the debug symbols?Or am i doing something wrong?

Answer 1

This means there's no available source/debug symbols for printf. You can use stepi to step into printf anyway, you'll only have disassembly available (use the disas command).

Answer 2

That's correct, you likely do not have debugging symbols available. Make sure libc-devel or similar is installed. Also, make sure to compile with -O0 to prevent optimization; optimizations make debugging more difficult to follow.