How to add a new structure to a GDB session

gdb-session.fish

❯ gcc -g minimal.c -o minimal

❯ sudo gdb minimal
Password:

(gdb) break main
Breakpoint 1 at 0x100000f90: file minimal.c, line 3.
(gdb) run
Starting program: /private/tmp/c-repl/minimal

Breakpoint 1, main () at minimal.c:3
3		int i = 1337;

### Ctrl-Z to suspend GDB session; edit structs.h and struct.c; and do:
### ❯ gcc -c -g structs.c -o structs.o
### then bring GDB back to foreground with `fg`

(gdb) add-symbol-file structs.o 0
add symbol table from file "structs.o" at
	.text_addr = 0x0
(y or n) y
Reading symbols from structs.o...done.
(gdb) p (struct sample *){23, 34}
$1 = (struct sample *) 0x100400000
(gdb) set $foo = *$1
(gdb) ptype $foo
type = struct sample {
    int i;
    int j;
}
(gdb) p $foo.i
$2 = 23
(gdb) p $foo.j
$3 = 34
(gdb) quit

gistfile1.txt

struct sample {
	int i;
	int j;
};

minimal.c

int main()
{
	int i = 1337;
	int j = 24;
	int k = i + j;
	return 0;
}

structs.c

#include "structs.h"
struct sample foo;