On 03/07/2012 12:02 PM, Ludovic Brenta wrote: > Reto Buerki wrote: >> On 03/07/2012 10:50 AM, Ludovic Brenta wrote: >>> Reto Buerki wrote: >>>>> * Build-Depend on gnat in addition to gnat-4.6 >>>> I don't exactly understand the rationale for this rule. In contrast to >>>> other packages the gnatgcc command is not needed to build dbusada. >>>> And I >>>> explicitly Build-Depend on the upcoming default compiler gnat-4.6 so >>>> ABI >>>> compatibility to other Ada packages is guaranteed. >>> >>> In section 4: >>> >>> "Rule: Package ‘gnat’ is the default Ada compiler for Debian. All >>> packages >>> containing Ada programs or libraries SHALL use this compiler." >>> >>> This rule makes it explicit that the package 'gnat-4.6' is NOT the >>> default >>> Ada compiler; the package 'gnat' is. >> >> And the package description of 'gnat' is: >> "This is an empty package that depends on the default Ada compiler for >> Debian, which is part of the GNU Compiler Collection." >> >> gnat currently depends on gnat-4.6, making it the 'current' default Ada >> compiler. >> >> I see no real (besides policy compliance) benefit here for depending on >> gnat in addition to gnat-4.6. The dbusada package defines that it needs >> exactly gnat-4.6 to build and that every package that depends on dbusada >> MUST also use this compiler. > > This is not sufficient. The policy is designed so that all Ada packages use > the *same* compiler. We want to prevent a situation where maintainer A > uploads package libfoo1-dev (depending on gnat-4.6) and maintainer B > uploads > package libbar2-dev (depending on gnat-4.7). This is not an error as > far as > the compiler is concerned but it is a policy violation because we want end > users to be able to link their executables against *all* libraries if they > so wish. Worse, nothing tells maintainer B about this violation. > > Now suppose maintainer B adds Build-Depends: gnat to libbar; the policy > violation immediately becomes apparent; the package FTBFS because it > does not > use the default compiler. > > In your case, you happen to be using the current default compiler "by > accident"; the policy requires you to use the default compiler > explicitly and > "by design".
Ok, I see your point. Thanks for the nice explanatory example. Maybe it would be good to include it in the Debian Ada policy as additional rationale for these rules. - reto -- To UNSUBSCRIBE, email to [email protected] with a subject of "unsubscribe". Trouble? Contact [email protected] Archive: http://lists.debian.org/[email protected]
