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=-3.3 required=5.0 tests=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 4125 invoked from network); 21 May 2020 20:31:17 -0000 Received: from mother.openwall.net (195.42.179.200) by inbox.vuxu.org with ESMTPUTF8; 21 May 2020 20:31:17 -0000 Received: (qmail 19588 invoked by uid 550); 21 May 2020 20:31:14 -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 18282 invoked from network); 21 May 2020 20:30:15 -0000 Date: Thu, 21 May 2020 22:22:53 +0200 From: Harald Welte To: musl@lists.openwall.com Message-ID: <20200521202253.GC601762@nataraja> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Subject: [musl] MUSL ignores__attribute__((constructor(priority))) ? Hi all! While investigating some really strange behavior of osmocom software on MUSL based systems (see https://osmocom.org/issues/4456) there are two observations: 1) if there are multiple libraries (in this example libosmocore and libtalloc, where libosmocore depends on libtalloc), the __attribute__((constructor)) functions are not called in inverse dependency order, i.e. the talloc ones are *not* called before those of libosmocore. 2) even when adding an explicit "priority" field like static __attribute__((constructor(65535))) void on_dso_load_ctx(void) the MUSL ld.so doesnt' seem to respect this, i.e. it still calls the constructor with the high priority value *before* the constructor of lower priority. This is not as specified in https://gcc.gnu.org/onlinedocs/gcc-4.7.0/gcc/Function-Attributes.html I don't know whether '1' is a bug (i.e. whether it is valid to assume constructors of libraries are executed in-line with library dependencies). However, I am quite convinced '2' is a bug. Regards, Harald p.s.: Please keep me in Cc, I'm not a subscriber to this list. -- - Harald Welte http://laforge.gnumonks.org/ ============================================================================ "Privacy in residential applications is a desirable marketing option." (ETSI EN 300 175-7 Ch. A6)