Control: tags -1 + patch
On Sat, 23 Oct 2021 at 21:23:19 +0200, Lucas Nussbaum wrote:
> During a rebuild of all packages in sid, your package failed to build
> on amd64.
>
> Relevant part (hopefully):
> > /<<PKGBUILDDIR>>/elements/gstqtvideosink/gstqtvideosinkbase.cpp: In static
> > member function ‘static GType GstQtVideoSinkBase::get_type()’:
> > /usr/include/glib-2.0/glib/gatomic.h:113:19: error: argument 2 of
> > ‘__atomic_load’ must not be a pointer to a ‘volatile’ type
The attached patch seems to resolve the FTBFS. I have not tested the
resulting binaries, but it's a trivial change following the same pattern
seen in many other GLib-based libraries.
The documentation of g_once_init_enter() now says:
While location has a volatile qualifier, this is a historical artifact
and the pointer passed to it should not be volatile.
volatile behaves like const, so it is valid to pass a pointer of type "T*"
to a function like g_once_init_enter() that is declared to take an argument
of type "volatile T*".
(Conversely, it would not be valid to pass a pointer of type "volatile T*"
to a function like g_mutex_lock() that is declared to take an argument
of type "T*" - again, this is the same rule as for const.)
smcv
From: Simon McVittie <s...@debian.org>
Date: Fri, 22 Jul 2022 02:10:35 +0100
Subject: Drop unnecessary volatile qualifier from g_once_init_enter()
argument
When compiling with gcc, g_once_init_enter() is a macro implemented
in terms of gcc's C++11-style atomic operations. Since gcc 11 it is
considered to be an error to pass a volatile pointer to these built-in
functions.
The volatile qualifier appears to have been added as a result of a
past misunderstanding about whether volatile is beneficial for
thread-safety in C/C++ (it is not).
Bug-Debian: https://bugs.debian.org/997252
---
elements/gstqtvideosink/gstqtvideosinkplugin.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/elements/gstqtvideosink/gstqtvideosinkplugin.h b/elements/gstqtvideosink/gstqtvideosinkplugin.h
index dc04671..a72c572 100644
--- a/elements/gstqtvideosink/gstqtvideosinkplugin.h
+++ b/elements/gstqtvideosink/gstqtvideosinkplugin.h
@@ -27,7 +27,7 @@ GST_DEBUG_CATEGORY_EXTERN(gst_qt_video_sink_debug);
#define DEFINE_TYPE_FULL(cpp_type, type_name, parent_type, additional_initializations) \
GType cpp_type::get_type() \
{ \
- static volatile gsize gonce_data = 0; \
+ static gsize gonce_data = 0; \
if (g_once_init_enter(&gonce_data)) { \
GType type = 0; \
GTypeInfo info; \
