Re: [PATCH 00/55] Hyper-V: code cleanup & prep for future changes

On Jan 22, 2021, at 12:07 PM, Matt Coleman <mcoleman(a)datto.com&gt; wrote: > On Jan 22, 2021, at 11:30 AM, Laine Stump <laine(a)redhat.com&gt; wrote: > > On 1/22/21 11:05 AM, Laine Stump wrote: >> 1) There are several cleanup functions in external libraries that in the past were only called after checking that the pointer was != NULL. g_autoptr cleanups need to handle being called with NULL as a NOP, and I'm concerned that these functions may not behave properly in that case. Can you either verify that it's safe to call them with NULL, or provide a wrapper function that checks for NULL and use that as the cleanup? > > I asked about item (2) on IRC just now, and danpb produced a short example program that proves it is okay to use values from auto-freed objects as the return value of a function. So there is only question (1) left. Let me know and I'll either push or wait for modified patches accordingly. For WsXmlDocH, GLib's documentation says that G_DEFINE_AUTOPTR_CLEANUP_FUNC() is NULL-safe: > The function will not be called if the variable to be cleaned up contains NULL. https://developer.gnome.org/glib/stable/glib-Miscellaneous-Macros.html#G-... For client_opt_t and filter_t, the third parameter to G_DEFINE_AUTO_CLEANUP_FREE_FUNC() was used to prevent the types' free functions from being called if they're NULL.