1.c

st@ubuntu:/media/st/CDROM$ gdb break 
GNU gdb (Ubuntu 7.11.1-0ubuntu1~16.5) 7.11.1
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break: No such file or directory.
(gdb) b 8048be0
No symbol table is loaded.  Use the "file" command.
Make breakpoint pending on future shared library load? (y or [n]) y
Breakpoint 1 (8048be0) pending.
(gdb) r
Starting program:  
No executable file specified.
Use the "file" or "exec-file" command.