From Fedora Project Wiki

Revision as of 23:21, 17 February 2011 by Rombobeorn (talk | contribs) (various improvements all over the page)

Packaging Ada programs and libraries

This document describes the current policies for packaging Ada programs and libraries for Fedora. These are Ada-specific amendments to the generic Packaging Guidelines. Ada packages must also conform to the Packaging Guidelines and the Review Guidelines.


Ada code in Fedora MUST be compiled using GNAT, the default Ada compiler in Fedora. (The package is called gcc-gnat.) The RPM macro %{GNAT_optflags} MUST be used in the compilation. It contains the standard Fedora optimization flags adapted to GNAT.

All packages that contain Ada code MUST build-require the fedora-gnat-project-common package to ensure that the necessary RPM macros are defined.

If the upstream source package comes with a build system, for example a GNAT project file or makefiles and a configuration script, then it's probably best to use that if possible. If not, it is recommended that the packager write a GNAT project file to control the compilation.

Devel packages

  • Ada library packages MUST have a -devel subpackage containing all the files that are necessary for compilation of code that uses the library. This includes Ada specification files (*.ads), Ada body files (*.adb), Ada library information files (*.ali) and GNAT project files (*.gpr).
  • The -devel package SHOULD NOT contain all the source files of the library, only those that are necessary for compilation of code that uses the library.
  • The -devel package SHOULD NOT contain any makefiles or other files that are only used for recompiling the library.
  • The -devel package SHOULD NOT contain any *.o files.

GNAT project files

  • The -devel package MUST contain one or more GNAT project files to be imported by other projects that use the library.
  • Project files MUST be architecture-independent. This means that the same project file must point to libraries in /usr/lib or /usr/lib64 depending on what target architecture the compiler is currently compiling for. This SHOULD be done by importing the "directories" project and using the variables defined there.
  • If the "directories" project is used, then the -devel package MUST have an explicit "Requires: fedora-gnat-project-common >= 2".
  • Project files MUST have an Externally_Built attribute equal to "true".

Here's an example of what a project file installed with a library may look like:

with "directories";
project Example is
   for Library_Name use "example";
   for Source_Dirs use (Directories.Includedir & "/example");
   for Library_Dir use Directories.Libdir;
   for Library_ALI_Dir use Directories.Libdir & "/example";
   for Externally_Built use "true";
end Example;

File placement

  • Ada source files in -devel packages (*.ads and *.adb) SHOULD be placed in the %{_includedir} directory or a subdirectory thereof. Placing them directly in %{_includedir} may be appropriate if there are very few of them in the package and their names include the name of the library. Otherwise they should usually be placed in a subdirectory, for example %{_includedir}/%{name}.
  • Ada library information files (*.ali) SHOULD be placed in a subdirectory of %{_libdir}, for example %{_libdir}/%{name}.
  • GNAT projects files (*.gpr) MUST be placed in the %{_GNAT_project_dir} directory or a subdirectory thereof. A subdirectory, for example %{_GNAT_project_dir}/%{name}, may be a good idea if there are lots of project files in the same package or if they have generic names. Otherwise they should usually be placed directly in %{_GNAT_project_dir}. The name of the library SHOULD be included either in the name of each project file or in the name of the subdirectory where the project files are placed.
The current value of %{_GNAT_project_dir} is /usr/lib/gnat. We intend to change it to /usr/share/gpr, which is more in line with FHS, if we can get GNAT to use that directory.

Rpmlint and Ada packages

Rpmlint is a program that checks packages for common problems. For Ada packages, some of the rpmlint messages, such as "executable-stack", can be disregarded. gcc because Ada and Pascal nested functions do not use trampolines.