My OS is Arch Linux, and the test.c program is very simple:
# cat test.c
#include <stdio.h>
int main(void) {
printf("Hello world!\n");
}
Compile it without -g option, and use file command to check the executable file information:
# gcc test.c
# file a.out
a.out: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 2.6.32, BuildID[sha1]=c7a538046222b5209d2daafbfc246de341a652d9, not stripped, with debug_info
The file command outputs "not stripped, with debug_info", but I don't use -g option during compilation. Use gdb to debug a.out:
# gdb a.out
GNU gdb (GDB) 7.12.1
Copyright (C) 2017 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
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Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
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Reading symbols from a.out...(no debugging symbols found)...done.
(gdb)
I can see gdb also prompts "Reading symbols from a.out...(no debugging symbols found)...done.".
Why does file command report "not stripped, with debug_info" of the executable file without "-g" option during compilation?