# Generate Listing and Map Files

Compiler-generated assembler output listings and linker-generated map files can help you understand the effects of compiler optimizations and see how your application is laid out in memory. They may also help you interpret the information provided in a stack trace at the time of an error.

## How to Generate Assembler Output

When compiling from the command line, specify the S option:

    ifort -S file.f90 ! Linux and macOS
    ifort file.f90 /S ! Windows OS

On Linux* and macOS systems, the resulting assembly file name has an `.s` suffix. On Windows* systems, the resulting assembly file name has an `.asm` suffix.

On Windows*, you can also use the Microsoft Visual Studio* Integrated Development Environment:

1. Select Project > Properties.

2. Click the Fortran tab.

3. In the Output Files category, change the Assembler Output settings according to your needs. You can choose from a number of options such as No Listing, Assembly-only Listing, and Assembly, Machine Code and Source.

## How to Generate a Link Map (.map) File

When compiling from the command line, specify the -Xlinker and -M options (Linux and macOS) or the /map (Windows) option:

    ifort file.f90 -Xlinker -M  ! Linux and macOS
    ifort file.f90 /map ! Windows

On Windows systems, you can also use the Visual Studio Integrated Development Environment:

1. Select Project>Properties.

2. Click the Linker tab.

3. In the Debug category, select Generate Map File.

## How to Generate a Source File Listing

You can use the list compiler option to create a listing of the source file. The listing can contain the following information: a display of INCLUDE files, a symbol list with a line number cross reference for each routine, and a list of compiler options used for the compilation.

Use the show compiler option to control the contents of the listing file.

Additionally, on Windows systems, you can use the Visual Studio Integrated Development Environment to create a source file listing:

1. Select Project > Properties.

2. Click the Fortran tab.

3. In the Output Files category, change the Source Listing setting to Yes.

Parent topic: Fortran Language Extensions

## See Also

show compiler option
list compiler option