From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 241983858C50; Mon, 17 Apr 2023 14:19:07 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 241983858C50 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1681741147; bh=xtNfqFiNoqwLwVcxstLzDubRpo6JflFE7q8b7wl/gr8=; h=From:To:Subject:Date:From; b=Wmek4RPufRJcpG2gfkoCfjGZ6NGDAIhNxhhynebT1dLOXqULIJsrbciu/lDEcv6t1 URFJUS5UIHWlNqiXGzRKtyZAJistFyKoFBDRBeJnEffmKQx1SskR06viAQJTWf8tGE EpITkVaKiNzV6vFZZQlcBRJSjhe645jpTxJAP1wI= From: "woodard at redhat dot com" To: libabigail@sourceware.org Subject: [Bug default/30363] New: Location of return type not tracked in ABI model. Date: Mon, 17 Apr 2023 14:19:06 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: libabigail X-Bugzilla-Component: default X-Bugzilla-Version: unspecified X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: woodard at redhat dot com X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: dodji at redhat dot com X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version bug_status bug_severity priority component assigned_to reporter cc target_milestone Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://sourceware.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 List-Id: https://sourceware.org/bugzilla/show_bug.cgi?id=3D30363 Bug ID: 30363 Summary: Location of return type not tracked in ABI model. Product: libabigail Version: unspecified Status: NEW Severity: normal Priority: P2 Component: default Assignee: dodji at redhat dot com Reporter: woodard at redhat dot com CC: libabigail at sourceware dot org Target Milestone: --- There are cases where the calling convention is different depending on the return type of a function for example when you have an array of a vector ty= pe, if it is annotated with the vector attribute, it will be passed by value ra= ther than as a pointer pushed on the stack. This is further complicated by specific rules about the size of a vector as presented in the source language in relation to the size of the vector registers. When this happens it can change the calling convention for the t= ype.=20 Unfortunately, compilers do not always get this exactly right: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D102027 So you can't just rel= y on the faithful implementation of the calling convention within the compiler to ensure that the vector is stored in the correct location.=20 Right now there is no real way, short of binary analysis to determine where= the return type of a subprogram is going to be located. Therefore we cannot det= ect these kinds of failures. There is a DWARF issue on this, https://dwarfstd.org/issues/221105.1.html When this is implemented we should make use of the location attribute for a subprogram to ensure that the comp= iler is putting the return time in the correct place. --=20 You are receiving this mail because: You are on the CC list for the bug.=