gfortran:tldr:4c541

This command is used to compile a Fortran source file (*.f90) and generate an assembly language file (*.s) using the GNU Fortran compiler (gfortran).

Here's an explanation of the components of the command:

• gfortran: This is the command to invoke the GNU Fortran compiler.
• -S: This option specifies that the compiler should generate assembly code instead of object code or an executable.
• ${path-to-source-f90}: This is a placeholder that should be replaced with the actual path to the Fortran source file you want to compile. It should end with the .f90 extension.

When you run this command, the GNU Fortran compiler will read the source file and produce an assembly language file that represents the low-level instructions equivalent to the original Fortran program. This can be helpful for understanding and analyzing the compiled code, as well as for debugging purposes.