gcc -o myfile file.c ./ myfile
gcc -o myfile file.c ./myfile
Contrary to popular belief, there is no command or syntax
./ that runs a file.
./myfile is simply the shortest path equivalent to
myfile that specifies a directory and therefore causes a shell to run it as-is, instead of trying to find its directory using $PATH.
Therefore, to run a file in the current directory, use
./myfile and not
ShellCheck is a static analysis tool for shell scripts. This page is part of its documentation.