https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77502
Rolf Eike Beer <e...@sf-mail.de> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |e...@sf-mail.de
--- Comment #4 from Rolf Eike Beer <e...@sf-mail.de> ---
Here is another case (all on a Gentoo system):
buildbot@castor ~ $ cat gnull.cpp
#include <glib.h>
#include <gtk/gtk.h>
void foo(GObject *g)
{
g_object_set_data(g, "b", GINT_TO_POINTER(FALSE));
}
buildbot@castor ~ $ sparc-unknown-linux-gnu-gcc-8.3.0 $(pkg-config --cflags
glib-2.0) $(pkg-config --cflags gtk+-2.0) -c -Wzero-as-null-pointer-constant
gnull.cpp
In file included from /usr/include/glib-2.0/glib/gtypes.h:32,
from /usr/include/glib-2.0/glib/galloca.h:32,
from /usr/include/glib-2.0/glib.h:30,
from gnull.cpp:1:
gnull.cpp: In function 'void foo(GObject*)':
/usr/lib/glib-2.0/include/glibconfig.h:90:50: warning: zero as null pointer
constant [-Wzero-as-null-pointer-constant]
#define GINT_TO_POINTER(i) ((gpointer) (glong) (i))
^
gnull.cpp:6:31: note: in expansion of macro 'GINT_TO_POINTER'
g_object_set_data(g, "b", GINT_TO_POINTER(FALSE));
Now with gcc 9.2.
buildbot@castor ~ $ gcc $(pkg-config --cflags glib-2.0) $(pkg-config --cflags
gtk+-2.0) -c -Wzero-as-null-pointer-constant gnull.cpp
# no diagnostics, fine with me
# and now I change the macro to use "glong" instead of "gint" in glibconfig.h I
get different output (same for gcc 8 and 9):
buildbot@castor ~ $ gcc $(pkg-config --cflags glib-2.0) $(pkg-config --cflags
gtk+-2.0) -c -Wzero-as-null-pointer-constant gnull.cpp
gnull.cpp: In function 'void foo(GObject*)':
gnull.cpp:7:1: warning: zero as null pointer constant
[-Wzero-as-null-pointer-constant]
7 | }
| ^
# that was my sparc with 32 bit userland, now my amd64 (openSUSE):
gcc (SUSE Linux) 7.4.1 20190424 [gcc-7-branch revision 270538]
eike@daneel:~$ gcc $(pkg-config --cflags glib-2.0) $(pkg-config --cflags
gtk+-2.0) -c -Wzero-as-null-pointer-constant gnull.cpp
In file included from /usr/include/glib-2.0/glib/gtypes.h:32:0,
from /usr/include/glib-2.0/glib/galloca.h:32,
from /usr/include/glib-2.0/glib.h:30,
from gnull.cpp:1:
gnull.cpp: In function ‘void foo(GObject*)’:
/usr/lib64/glib-2.0/include/glibconfig.h:90:50: warning: zero as null pointer
constant [-Wzero-as-null-pointer-constant]
#define GINT_TO_POINTER(i) ((gpointer) (glong) (i))
^
gnull.cpp:6:31: note: in expansion of macro ‘GINT_TO_POINTER’
g_object_set_data(g, "b", GINT_TO_POINTER(FALSE));
^~~~~~~~~~~~~~~
When I have the relevant code in a greater function (
https://github.com/osm2go/osm2go/blob/6a7b955053ef9938f4be7b7ca8eacb99e4c426cf/src/platforms/gtk/osm_upload_dialog.cpp#L143
) this does _not_ warn on my PC, but it warns on the sparc.
