Re: [Qemu-devel] [PATCH] qga/commands-posix.c: Use correct types with g_base64_decode()

[Peter Maydell <peter.maydell@linaro.org>]

On 14 April 2015 at 14:38, Thomas Huth <thuth@redhat.com> wrote:
> Am Wed,  8 Apr 2015 21:02:49 +0100
> schrieb Peter Maydell <peter.maydell@linaro.org>:
>
>> The second argument of g_base64_decode() is a 'gsize *', not a
>> 'size_t *'. Some compilation environments (like building 32-bit PPC
>> binaries on a PPC64 system) will complain about the mismatch:
>>
>>   CC    qga/commands-posix.o
>> qga/commands-posix.c: In function 'qmp_guest_set_user_password':
>> qga/commands-posix.c:1908:5: error: passing argument 2 of 'g_base64_decode' from incompatible pointer type [-Werror]
>> In file included from /usr/include/glib-2.0/glib.h:37:0,
>>                  from qga/commands-posix.c:14:
>> /usr/include/glib-2.0/glib/gbase64.h:49:9: note: expected ‘gsize *’ but argument is of type ‘size_t *’
>>
>> (We previously fixed errors of this type in commit 3d1bba20.)
>>
>> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
>> ---
>>  qga/commands-posix.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/qga/commands-posix.c b/qga/commands-posix.c
>> index ba8de62..9fde348 100644
>> --- a/qga/commands-posix.c
>> +++ b/qga/commands-posix.c
>> @@ -1901,7 +1901,7 @@ void qmp_guest_set_user_password(const char *username,
>>      int status;
>>      int datafd[2] = { -1, -1 };
>>      char *rawpasswddata = NULL;
>> -    size_t rawpasswdlen;
>> +    gsize rawpasswdlen;
>>      char *chpasswddata = NULL;
>>      size_t chpasswdlen;
>>
>
> I've just ran into this issue as well on my x86 laptop when playing
> around with "--extra-cflags=-m32"... so should this be fixed for the
> 2.3 release already? I didn't spot your patch on the master branch
> yet...

No, this is not-for-2.3. I think that the issue here is that
merely adding -m32 isn't sufficient, because pkg-config when
run by configure will end up pointing at a bunch of incorrect
glib includes (for x86-64, not i386). So the actual solution
is to give configure the right pkg-config, and then gsize and
size_t are the same. There's a patch by John Snow for
configure on-list for that.

-- PMM