Hi,
the following discussion is from kvm-ppc-devel, but it is actually an qemu
discussion so I move th topic to qemu-devel.
The original thread is cited in the mail below, in short the issue is the
following:
Newer gcc versions generate warnings about implicit casts between different
signed pointers.
That hits a lot of qemu code at least what I saw it compiling for ppc or x86.
So my question is, is there already a preferred qemu approach to get rid of
these warnings
either the -Wno-pointer-sign solution like in the kernel or something else (I
did not find
anything like that in the latest cvs snapshot or on this list)?
--- thread from kvm-ppc-devel ---
Jimi Xenidis wrote:
On Jan 11, 2008, at 10:04 AM, Hollis Blanchard wrote:
On Fri, 2008-01-11 at 14:14 +0100, Christian Ehrhardt wrote:
Hi,
maybe its an issue of my build environment only, but when I compile
kvm-userspace for our platform I see a lot of warnings like that in
the qemu code:
warning: pointer targets in passing argument 3 of
'PPC_NVRAM_set_params' differ in signedness
The reason is that some code defines function prototypes and variables
with the type "const unsigned char*" and then assigns a literal like
"PPC" to it. But per default our platform seems to have "const signed
char*" for literals and so we get a lot of annoying warnings. E.g.
nearly every line in qemu/target-ppc/translate.c.
Should we do anything to prevent these Warnings or do you even see
those ?
That warning only appears in recent versions of gcc. In fact I believe
there are 3 different types: char *, unsigned char *, and signed char *,
and implicitly casting between them generates the warnings. :(
[...]
It's a qemu issue. If you want to fix it, you should bring it up on
qemu-devel and see what they think about it.
this is what:
# disable pointer signed / unsigned warnings in gcc 4.0
KBUILD_CFLAGS += $(call cc-option,-Wno-pointer-sign,)
In linux/Makefile is for.
-JX
--
Grüsse / regards,
Christian Ehrhardt
IBM Linux Technology Center, Open Virtualization
