C does not permit an initialiser expression on a variable-length array
(C99 Section 6.7.9 constraint: "The type of the entity to be initialized
shall not be a variable length array type").
vfio_pci_irq_set() declared:
u8 buf[sizeof(struct vfio_irq_set) + sizeof(int) * count] = {};
where `count` is a runtime function parameter, making `buf` a VLA.
GCC rejects this with (tried with GCC-9.4.0):
error: variable-sized object may not be initialized
Fix by removing the `= {}` initialiser and inserting an explicit
memset() immediately after the declaration. memset() on a VLA is
perfectly legal and achieves the same zero-initialisation on all
conforming C implementations.
Fixes: 19faf6fd96 ("vfio: selftests: Add a helper library for VFIO selftests")
Cc: stable@vger.kernel.org
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: David Matlack <dmatlack@google.com>
Signed-off-by: Manish Honap <mhonap@nvidia.com>
Link: https://lore.kernel.org/r/20260317051402.3725670-1-mhonap@nvidia.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
4f42d71670