From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,FREEMAIL_FROM autolearn=unavailable autolearn_force=no version=3.4.4 Path: eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!news.eternal-september.org!news.eternal-september.org!feeder.eternal-september.org!aioe.org!.POSTED!not-for-mail From: Victor Porton Newsgroups: comp.lang.ada Subject: Re: Strict aliasing, is it OK? Date: Tue, 04 Jul 2017 23:13:50 +0300 Organization: Aioe.org NNTP Server Message-ID: References: NNTP-Posting-Host: 5v2/mjF2EZ/Zj3uAcepXoA.user.gioia.aioe.org Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7Bit X-Complaints-To: abuse@aioe.org User-Agent: KNode/4.14.10 X-Notice: Filtered by postfilter v. 0.8.2 Xref: news.eternal-september.org comp.lang.ada:47290 Date: 2017-07-04T23:13:50+03:00 List-Id: Victor Porton wrote: > I do unchecked conversions (in both directions) between Handle_Type and > My_Dummy_Access. > > Everytime I refer to Handle_Type, it is real Handle_Type. > > But there is several Handle_Type (defined in different packages). Let us > denote them Handle_Type1, Handle_Type2, Handle_Type3, ... > > When I refer to My_Dummy_Access it may be any one of Handle_Type1, > Handle_Type2, Handle_Type3, ... > > But I never convert Handle_TypeN into Handle_TypeM for N/=M. > > I also never use My_Dummy_Access to anything except to convert it into > Handle_TypeX. Or (I forgotten that) I also may pass My_Dummy_Access to an imported C function. > Question: Are these restrictions enough for the compiler to the right > thing (that is not something counterintuitive)? > > What is the right fix for the warning? Shall I add pragma > No_Strict_Aliasing? > -- Victor Porton - http://portonvictor.org