On Fri, Sep 10, 2021 at 02:26:32PM +0200, Tim Wiederhake wrote:
On Fri, 2021-09-10 at 11:53 +0100, Daniel P. Berrangé wrote:
On Fri, Sep 10, 2021 at 12:45:43PM +0200, Tim Wiederhake wrote:
Workaround for a bug in clang. Clang emits an unused-variable warning if the variable is only accessed on scope exit by a destructor function. Note that gcc does not exhibit this behavior.
See https://bugs.llvm.org/show_bug.cgi?id=3888 and https://bugs.llvm.org/show_bug.cgi?id=43482.
Signed-off-by: Tim Wiederhake <twiederh@redhat.com> --- src/util/glibcompat.h | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+)
diff --git a/src/util/glibcompat.h b/src/util/glibcompat.h index 697687b967..ea486e32d5 100644 --- a/src/util/glibcompat.h +++ b/src/util/glibcompat.h @@ -86,3 +86,22 @@ char *vir_g_strdup_vprintf(const char *msg, va_list args) #define g_fsync vir_g_fsync void vir_g_source_unref(GSource *src, GMainContext *ctx); + +/* + * Workaround for a bug in clang. Clang emits an unused-variable warning if the + * variable is only accessed on scope exit by a destructor function. See + * https://bugs.llvm.org/show_bug.cgi?id=3888 and + * https://bugs.llvm.org/show_bug.cgi?id=43482. + */ +#if defined(__clang__) +# undef g_autoptr +# define g_autoptr(TypeName) _GLIB_CLEANUP(_GLIB_AUTOPTR_FUNC_NAME(TypeName)) _GLIB_AUTOPTR_TYPENAME(TypeName) G_GNUC_UNUSED +# undef g_autolist +# define g_autolist(TypeName) _GLIB_CLEANUP(_GLIB_AUTOPTR_LIST_FUNC_NAME(TypeName)) _GLIB_AUTOPTR_LIST_TYPENAME(TypeName) G_GNUC_UNUSED +# undef g_autoslist +# define g_autoslist(TypeName) _GLIB_CLEANUP(_GLIB_AUTOPTR_SLIST_FUNC_NAME(TypeName)) _GLIB_AUTOPTR_SLIST_TYPENAME(TypeName) G_GNUC_UNUSED +# undef g_autoqueue +# define g_autoqueue(TypeName) _GLIB_CLEANUP(_GLIB_AUTOPTR_QUEUE_FUNC_NAME(TypeName)) _GLIB_AUTOPTR_QUEUE_TYPENAME(TypeName) G_GNUC_UNUSED +# undef g_auto +# define g_auto(TypeName) _GLIB_CLEANUP(_GLIB_AUTO_FUNC_NAME(TypeName)) TypeName G_GNUC_UNUSED +#endif /* __clang__ */
This patch should not be needed anymore afaik since we addressed the problems that were triggering clang.
Did you see patches 9 to 12? They introduce more "only used on scope exit" variables that trigger clangs warning otherwise.
Why aren't they following the approach that Peter used to address this though, by adding the G_GNUC_UNUSED annotations to the usage sites ? We should only re-define the g_auto* macros if we have first submitted this change to GLib upstream and they merged it. Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|