Re: Library file locations (was: Debian Policy for Ada, Second Edition)

[Ludovic Brenta <ludovic@ludovic-brenta.org>]

Tapio Kelloniemi <spam18@thack.org> writes:
>>In particular, /usr/local is, by definition, for use by the system
>>administrator, and therefore falls outside the scope of any policy
>>defined by the operating system.
>
> Why GCC then looks for headers in /usr/local/include? Because many packages
> are installed in /usr/local by sysadmins and because /usr/local/include
> is in GCC's default search path, other packages can link against 
> packages installed by admin without using absolute paths. Has anyone ever
> seen C code like:
> #include "/usr/local/include/readline/readline.h"

No but I often see:

gcc -c -I/usr/local/include foo.c

> What comes to setting ADA_PROJECT_PATH, I think it is just setting
> one more redundant environment variable. Editing a text file is much
> more elegant solution.

But you would normally set ADA_PROJECT_PATH from within a Makefile, so
your objection is weak.

>> If you want GNAT to look in some
>>particular subdirectory of /usr/local, then use ADA_PROJECT_PATH or
>>"with" the fully qualified file name of your project files.
>
> Let us think that I'm to publish my application A in source format on my
> web site. The package is built with a command like:
> gnatmake -PA
>
> If my project file contains something like:
> with "/usr/share/ada/adainclude/florist.gpr";
> with "/...";
> with "/...";
>
> Suddenly I'll get a lot of complaints that compiling my application is very
> frustrating because users must hassle with the absolute path definitions
> in my project file.

As I said, gnat-4.1 will look in /usr/share/ada/adainclude by default,
so you will not need absolute paths.  So your objection is addressed.

Secondly, even if gnat didn't look in that directory by default,
nobody could blame you for following the GNAE standard, could they?

>>So, what exactly is the problem?
>
> Easy usage of libraries, no matter whether they are installed by a
> sysadmin or a distro.

And the Debian Policy for Ada addresses just that problem.  I meant,
what is the *remaining* problem after you've read the Debian Policy
for Ada?

-- 
Ludovic Brenta.