Bernhard Kleine <[email protected]> writes: > Am 13.11.2016 um 22:51 schrieb Simon Albrecht: >> On 13.11.2016 22:49, Noeck wrote: >>> Both >>> >>> \relative c { >>> <f ces' es>1~-- | >>> <f ces' des> | >>> } >>> >>> and >>> >>> \relative { >>> <cis' e>1~-- | >>> <cis d> | >>> } >>> >>> are compiled without problems here (2.19.49, Ubuntu 16.10, 64bit). >> >> OK, so it’s a bug already fixed. >> >> Best, Simon > But withour knowing it!
I wouldn't say that. This is commit 93f3d637efbc038b837cf64fae0872e873e4f039 Author: David Kastrup <[email protected]> Date: Fri Sep 2 23:11:53 2016 +0200 Issue 4965: Create and use Grob::parent_relative This function checks for the existence of a Grob parent before calculating a coordinate relative to it. This should hopefully clean up the most relevant problems caused by issue 4814 and the original GCC 6 optimization causing it. fixed in 2.19.48. Conversely, issue 4814 was addressed in 2.19.46 by commit b0dce76daf27721ba157cd2ac5d7662d4c8d75f8 Author: Guido Aulisi <[email protected]> Date: Fri Jul 22 15:26:29 2016 +0200 Issue 4814: grob.cc segfaults with gcc6 From the release notes of GCC 6: Optimizations remove null pointer checks for this When optimizing, GCC now assumes the this pointer can never be null, which is guaranteed by the language rules. Invalid programs which assume it is OK to invoke a member function through a null pointer (possibly relying on checks like this != NULL) may crash or otherwise fail at run time if null pointer checks are optimized away. With the -Wnull-dereference option the compiler tries to warn when it detects such invalid code. If the program cannot be fixed to remove the undefined behavior then the option -fno-delete-null-pointer-checks can be used to disable this optimization. That option also disables other optimizations involving pointers, not only those involving this. As a consequence, we cannot call a member function on a prospective null pointer (which actually is a bad idea for a number of other reasons, like when anything tries accessing the vtable) and then try sorting out the condition in the routine itself. This problem was first observed with Fedora 24. The Ubuntu GCC6 prerelease does not show this problem; presumably the respective optimization has been disabled in the Ubuntu/Debian packaging because of affecting other programs. Commit-message-by: David Kastrup <[email protected]> Signed-off-by: David Kastrup <[email protected]> and the fix was relying on incomplete analysis, making it responsible for the damage reported here. -- David Kastrup _______________________________________________ lilypond-user mailing list [email protected] https://lists.gnu.org/mailman/listinfo/lilypond-user
