macros: verify if __alloc_size__ works with clang

So we can avoid using using an attribute not supported for the compiler.

warning:
../spice-common/common/mem.h:91:80: warning: unknown attribute
'__alloc_size__' ignored [-Wunknown-attributes]

void *spice_malloc0_n(size_t n_blocks, size_t n_block_bytes)
SPICE_GNUC_MALLOC SPICE_GNUC_ALLOC_SIZE2(1,2);

../spice-common/spice-protocol/spice/macros.h:52:52: note: expanded
from macro 'SPICE_GNUC_ALLOC_SIZE2'

 #define SPICE_GNUC_ALLOC_SIZE2(x,y) __attribute__((__alloc_size__(x,y)))
                                                    ^

0 files changed, 0 insertions, 0 deletions