Adding or subtracting a value to a pointer makes a new pointer of unknown type. So typeof() is replaced by (void*) in RTE_PTR_ADD() and RTE_PTR_SUB().
But RTE_PTR_ALIGN_* macros have in their explicit API to return a pointer of the same type. Since RTE_PTR_ALIGN_CEIL is based on RTE_PTR_ADD, a typeof() is added to keep the original behaviour. Signed-off-by: Thomas Monjalon <thomas.monjalon at 6wind.com> --- lib/librte_eal/common/include/rte_common.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/lib/librte_eal/common/include/rte_common.h b/lib/librte_eal/common/include/rte_common.h index 96aeeee..d2e096d 100644 --- a/lib/librte_eal/common/include/rte_common.h +++ b/lib/librte_eal/common/include/rte_common.h @@ -70,12 +70,12 @@ extern "C" { /** * add a byte-value offset from a pointer */ -#define RTE_PTR_ADD(ptr, x) ((typeof(ptr))((uintptr_t)ptr + (x))) +#define RTE_PTR_ADD(ptr, x) ((void*)((uintptr_t)ptr + (x))) /** * subtract a byte-value offset from a pointer */ -#define RTE_PTR_SUB(ptr, x) ((typeof(ptr))((uintptr_t)ptr - (x))) +#define RTE_PTR_SUB(ptr, x) ((void*)((uintptr_t)ptr - (x))) /** * get the difference between two pointer values, i.e. how far apart @@ -131,7 +131,7 @@ rte_align_floor_int(uintptr_t ptr, uintptr_t align) * must be a power-of-two value. */ #define RTE_PTR_ALIGN_CEIL(ptr, align) \ - RTE_PTR_ALIGN_FLOOR(RTE_PTR_ADD(ptr, align - 1), align) + RTE_PTR_ALIGN_FLOOR((typeof(ptr))RTE_PTR_ADD(ptr, align - 1), align) /** * Macro to align a value to a given power-of-two. The resultant value -- 1.7.10.4