Without main function, compilation fails.

[OwenGrumbles]

When compiling with:

gcc -o hashmap hashmap.c

I get this error:

/usr/bin/ld: /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/../../../../lib/Scrt1.o: in function `_start':
(.text+0x1b): undefined reference to `main'
collect2: error: ld returned 1 exit status

Adding main function leads to successful compilation.

[BanceDev]

thats because you're trying to make an executable out of the hashmap source file. If your goal is to build the shell check out the build instructions. This project uses premake for the build system.