From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 659323858434; Thu, 24 Feb 2022 12:16:26 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 659323858434 From: "gprocida at google dot com" To: libabigail@sourceware.org Subject: [Bug default/26646] unexpected declaration-only types Date: Thu, 24 Feb 2022 12:16:26 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed 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: gprocida at google dot com X-Bugzilla-Status: ASSIGNED 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: Message-ID: In-Reply-To: References: 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 X-BeenThere: libabigail@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Mailing list of the Libabigail project List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 24 Feb 2022 12:16:26 -0000 https://sourceware.org/bugzilla/show_bug.cgi?id=3D26646 --- Comment #24 from gprocida at google dot com --- Hi. I ran some quick tests - the libabigail test suite and on the two kernels. Good * vmlinux3 and vmlinux4 get ABIs which are the same, including declaration-= only / fully-defined status * both have more fully-defined types than the previous iteration (around 9) * a Linux test case looks better (some declaration-only duplicates vanish) Not so good * struct can_dev_rcv_lists is now declaration-only (w.r.t. to the original baseline ABIs) * struct prefix_info too (w.r.t. an intermediate code version) * there is a test case regression (nmap) I'll do some more digging, but probably nothing directly with these two typ= es right now. Someone here pointed out to me that Clang and GCC have "type homing" logic = to reduce the definitions that get emitted into DWARF to what's needed (leaving some types declaration-only). The relevant flags (to disable this) are -fstandalone-debug and -femit-class-debug-always, respectively. You might decide that if either of these flags makes a difference to libabi= gail output then there's a bug somewhere in the compiler, linker or libabigail. = Or it might be the case that disabling the logic exposes the types behind opaq= ue pointers in a way which is unwanted. In any case, I'm going to see what sort of impact -fstandalone-debug has on ABIs and kernel build time and size. Regards, Giuliano. --=20 You are receiving this mail because: You are on the CC list for the bug.=