Why there are serval different versions related to GLIBC when dumping the symbols of a program by nm whereas the program is built with GLIBC_2.23?

[Adhemerval Zanella]

On 16/08/2020 22:46, 孙世龙 sunshilong via Libc-help wrote:
> Hi, list
> 
> Why there are serval different versions related to GLIBC when dumping
> the symbols of a program by nm whereas the program is built with
> GLIBC_2.23?
> 
> Here are the dumping symbols:
> nm ./test1 | grep -i glibc
>                  U drand48@@GLIBC_2.2.5
>                  U exit@@GLIBC_2.2.5
>                  U __fprintf_chk@@GLIBC_2.3.4
>                  U gettimeofday@@GLIBC_2.2.5
>                  U __libc_start_main@@GLIBC_2.2.5
>                  U malloc@@GLIBC_2.2.5
>                  U __printf_chk@@GLIBC_2.3.4
>                  U sqrt@@GLIBC_2.2.5
>                  U __stack_chk_fail@@GLIBC_2.4
> 00000000006020c0 B stderr@@GLIBC_2.2.5
>

This is the initial version when the symbol was added.  And it can vary
for different architectures (with different baseline versions).