From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-3.1 required=5.0 tests=DKIM_INVALID,DKIM_SIGNED, MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 32420 invoked from network); 7 Nov 2021 18:20:41 -0000 Received: from mother.openwall.net (195.42.179.200) by inbox.vuxu.org with ESMTPUTF8; 7 Nov 2021 18:20:41 -0000 Received: (qmail 2039 invoked by uid 550); 7 Nov 2021 18:20:39 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Reply-To: musl@lists.openwall.com Received: (qmail 2019 invoked from network); 7 Nov 2021 18:20:39 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1636309226; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=IWhF807wVHr2DHEAUvHog8BHiF7ooLQ7a2AZESHpC8E=; b=TDR4Vex7hU6SFKGgaoJ4vSotxr0RWNZkxUYbgWsHtu+D2+k5ZEK2F8S1Gi8Y9KO+gTCLaX sjHN0SeZdvvB1rvEBUiUNed6VC+xhSvbBvwk2uJVAyJjemB8TnAv+AueOFvr5M29ZgbbzX LlpgLXDh75d8YBhcMr/dO81vpHqw7B4= X-MC-Unique: A86IQWjDNZyJjaCPhrF8qg-1 From: Florian Weimer To: James Y Knight Cc: musl@lists.openwall.com References: Date: Sun, 07 Nov 2021 19:20:21 +0100 In-Reply-To: (James Y. Knight's message of "Sun, 7 Nov 2021 12:37:09 -0500") Message-ID: <87lf1z6d5m.fsf@oldenburg.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=fweimer@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain Subject: Re: [musl] add noexcept to all functions please * James Y. Knight: > Glibc defines macros for this purpose, which expand into "throw()" in > C++ and "__attribute__((__nothrow__))" in GCC-C. The latter is only > useful in conjunction with an extremely-rarely-used feature, C code > built with -fexceptions enabled, and is thus probably ignorable. We build our distributions with -fexceptions -fasynchronous-unwind-tables. These features have real uses out there (although -fasynchronous-unwind-tables is probably more important for performance analysis and diagnostics). With glibc, -fexceptions is desirable to avoid unprotected function pointers on the stack in conjunction with POSIX cancellation handlers (which can be relevant even if unwinding does not happen). I believe the musl cancellation implementation does not use DWARF unwinding. I do not know if it cancellation handlers have the same hardening gap as glibc's with setjmp-based unwinding. Thanks, Florian