gnatls recognizes the following switches:
Display copyright and version, then exit disregarding all other options.
--version was not used, display usage, then exit disregarding
all other options.
Consider all units, including those of the predefined Ada library.
Especially useful with
List sources from which specified units depend on.
Output the list of options.
Only output information about object files.
Only output information about source files.
Only output information about compilation units.
Take as arguments the files listed in text file
file may contain empty lines that are ignored.
Each nonempty line should contain the name of an existing file.
Several such switches may be specified simultaneously.
Source path manipulation. Same meaning as the equivalent
flags (Switches for gnatmake).
dir at the beginning of the project search dir.
Specifies the default location of the runtime library. Same meaning as the
gnatmake flag (Switches for gnatmake).
Verbose mode. Output the complete source, object and project paths. Do not use the default column layout but instead use long format giving as much as information possible on each requested units, including special characteristics such as: