This program did not have certain dynamic linking related sections because we linked it minimally with ld.
However, if you compile a C hello world with GCC 8.2:
gcc -o main.out main.c
some other interesting sections would appear.
Contains the path to the dynamic loader, i.e. /lib64/ld-linux-x86-64.so.2 in Ubuntu 18.10. Explained at: stackoverflow.com/questions/8040631/checking-if-a-binary-compiled-with-static/55664341#55664341
Contains a lot of different flag masks.
Seems to be a GNU Binutils extension
Determines if an executable is a position independent executable (PIE).
Seems to be informational only, since not used by Linux kernel 5.0 or glibc 2.29.