From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 19C7A3854819; Mon, 14 Dec 2020 13:21:26 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 19C7A3854819 From: "muecker at gwdg dot de" To: gcc-bugs@gcc.gnu.org Subject: [Bug c/98217] Prefer a warning for when VLAs declared on stack Date: Mon, 14 Dec 2020 13:21:25 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: c X-Bugzilla-Version: 10.2.0 X-Bugzilla-Keywords: diagnostic X-Bugzilla-Severity: enhancement X-Bugzilla-Who: muecker at gwdg dot de X-Bugzilla-Status: WAITING X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org 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://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: gcc-bugs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-bugs mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 14 Dec 2020 13:21:26 -0000 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D98217 --- Comment #10 from Martin Uecker --- (for C++ compatibility, there is: -Wc++XX-compat ) So since Xmas is coming:=20 - I would also like an option to allocate VLAs of unbounded size larger tha= n X on the heap.=20 - Better code generation for VLAs. Maybe VLAs of small bounded size could be automatically transformed into regular arrays for the purpose of code generation. IIRC, Linux kernel replaced some VLAs on the stack with fixed-sized buffers= on the stack. But this increases stack size and reduces type safety.=