BPF backend doesn't generate some of the symtab informations

Hello,

I'm now trying to extract some .symtab information such as source C file name (STT_FILE) from BPF ELF
object which is compiled from following C code by clang, but it seems the generated information is different depends
on the target.

=== test.c ====
#include <stdint.h>

uint64_t test(uint64_t a) {
return a + 1;
}