gcc won't create executable file on linux terminal [Solved] [closed]

I am trying to create an executable file from multiple C source files on linux terminal using gcc. I managed to create the object files but the executable file won't show up. This is what I have been running in terminal:

gcc -Wall -c commandLine.c main.c commandLine.h

The above creates the object files.

gcc commandLine.o main.o -o executable

The above is supposed to create the executable file but no executable file shows up in my directory.This is what is then printed in terminal:

/usr/bin/ld: warning: cannot find entry symbol xecutable; defaulting to 0000000000001740main.o: In function `main':main.c:(.text+0x2897): undefined reference to `CreateVariable'collect2: error: ld returned 1 exit status