From: Markus Ongyerth <w...@ongy.net> In  it was pointed out, that the proposed patch breaks code, that does not remove their listener from a wl_signal list, but just free()s them.
From libwayland's perspective, this has never been different. People just got lucky. wl_priv_signal_emit will touch the recently free()d memory again IFF there is another listener behind it in the signal list. The attached patch makes this obvious under valgrind (memcheck). I would prefer if it failed the testcase, but I'm not sure how to do that (some sanitizer options?). Going forward, it would be relativly easy to add a special case for single listener signals to the original patch, but in the rather lengthy discussion we had earlier, we concluded that we should try to fix clients from libwayland side. But this could cause problems for code that uses wl_signal and wl_signal_emit internally, since that should actually not touch any previously called wl_listener in the signal list (until next emit). A secondary emit_destroy (emit_final) path as suggested in  seems to be the better way.  https://lists.freedesktop.org/archives/wayland-devel/2018-February/037168.html  https://lists.freedesktop.org/archives/wayland-devel/2018-February/037203.html Markus Ongyerth (1): tests: Add free-without-remove test Makefile.am | 3 ++ tests/free-without-remove.c | 70 +++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 73 insertions(+) create mode 100644 tests/free-without-remove.c -- 2.16.2 _______________________________________________ wayland-devel mailing list email@example.com https://lists.freedesktop.org/mailman/listinfo/wayland-devel