There is no magic in a C compiler, it's not like the string literals in your source somehow disappear. An ELF executable has them sitting in the data (or text)

There is no magic in a C compiler, it's not like the string literals in your source somehow disappear. An ELF executable has them sitting in the data (or text) segment, so it's not a feat of engineering to pull them out. objdump, or even just running "strings yourbinary" will display them.