Re: project file syntax

[Robert A Duff <bobduff@shell01.TheWorld.com>]

agent@drrob1.com writes:

> As an exercise for myself, I'm converting an rpn calculator I wrote in
> modula-2 to Ada.  I have already debugged several modules, such as
> tknrtnsa, timliba and environa.  Now I want to debug 2 modules,
> hpcalca and rpna.  I call this project file rpna.gpr
>
> project rpna is
>   for Source_Files use ("rpna.adb","hpcalca.ads","hpcala.adb");   for

I suggest using the default naming convention, and leaving out the "for
Source_Files...".  Then your project will contain all source files
whose names match *.ads and *.adb.

You don't want to edit your project file every time you add a new source
file (or rename or delete one).

> Source_Dirs use (".", "./**");
>   for Main use ("rpna");   
>
>   package Builder is
>     for Default_Switches ("Ada")
>         use ("-g");
>   end Builder;
>
>   package Compiler is
>     for Default_Switches ("Ada")
>        use ("-fstack-check",
>             "-gnatVa",
>             "-g",
>             "-gnato",
>             "-gnatf",
>             "-gnatwu",

Consider using -gnatwa or -gnatwae.

>             "-gnat2012");
>   end Compiler;
>
> end rpna;
>
>
> I get errors that the modules I previously wrote cannot be found. That
> is, tknrtnsa, timliba and environa cannot be found.

Right.  Your project contains exactly 3 source files, and if they say
"with tknrtnsa", it won't find tknrtnsa.ads.

>...If I have these
> re-compiled by putting them in the Source_Files list, that works.  But
> it strikes me as I am not understanding something about project files.
>
> How do I write a project file to not have to recompile packages that I
> know already work, and for which I have the .ali and .o files?

That happens automatically.  gprbuild will [re]compile just the files
that need to be [re]compiled.  If you already have .ali and .o files
from a previous run of gprbuild, and they are up to date, those will not
be recompiled.  You shouldn't be trying to tell it which files need to
be recompiled -- it figures that out based on timestamps and .ali files.

You don't need to run gcc directly; just use gprbuild.

- Bob