Re: [dpdk-dev] [PATCH] headers: typeof -> __typeof__ to unbreak C++11 code

["Ananyev, Konstantin" <konstantin.ananyev@intel.com>]

> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Simon Kagstrom
> Sent: Wednesday, February 25, 2015 1:29 PM
> To: dev@dpdk.org
> Subject: [dpdk-dev] [PATCH] headers: typeof -> __typeof__ to unbreak C++11 code
> 
> When compiling C++11-code or above (--std=c++11), the build fails with
> lots of
> 
>   rte_eth_ctrl.h:517:3: note: in expansion of macro RTE_ALIGN
>     (RTE_ALIGN(RTE_ETH_FLOW_MAX, UINT32_BIT)/UINT32_BIT)
>     ^
> 
> When reading the GCC info pages, I get the feeling that __typeof__ is
> a better choice, and that indeed works when including the headers in
> C++ files (--std=c++11).
> 
> There are some typeof()s left in C files, the patch only touches the
> public API.
> 
> Signed-off-by: Simon Kagstrom <simon.kagstrom@netinsight.net>
> ---
>  lib/librte_acl/acl_vect.h                  |  8 ++++----
>  lib/librte_eal/common/include/rte_common.h | 17 +++++++++--------
>  lib/librte_eal/common/include/rte_pci.h    |  2 +-
>  3 files changed, 14 insertions(+), 13 deletions(-)
> 
> diff --git a/lib/librte_acl/acl_vect.h b/lib/librte_acl/acl_vect.h
> index 6cc1999..de47071 100644
> --- a/lib/librte_acl/acl_vect.h
> +++ b/lib/librte_acl/acl_vect.h
> @@ -52,8 +52,8 @@ extern "C" {
>   * hi - contains high 32 bits of given N transitions.
>   */
>  #define	ACL_TR_HILO(P, TC, tr0, tr1, lo, hi)                        do { \
> -	lo = (typeof(lo))_##P##_shuffle_ps((TC)(tr0), (TC)(tr1), 0x88);  \
> -	hi = (typeof(hi))_##P##_shuffle_ps((TC)(tr0), (TC)(tr1), 0xdd);  \
> +	lo = (__typeof__(lo))_##P##_shuffle_ps((TC)(tr0), (TC)(tr1), 0x88);  \
> +	hi = (__typeof__(hi))_##P##_shuffle_ps((TC)(tr0), (TC)(tr1), 0xdd);  \
>  } while (0)
> 
> 
> @@ -74,8 +74,8 @@ extern "C" {
>  	addr, index_mask, next_input, shuffle_input,		\
>  	ones_16, range_base, tr_lo, tr_hi)               do {	\
>  								\
> -	typeof(addr) in, node_type, r, t;			\
> -	typeof(addr) dfa_msk, dfa_ofs, quad_ofs;		\
> +	__typeof__(addr) in, node_type, r, t;			\
> +	__typeof__(addr) dfa_msk, dfa_ofs, quad_ofs;		\
>  								\
>  	t = _##P##_xor_si##S(index_mask, index_mask);		\
>  	in = _##P##_shuffle_epi8(next_input, shuffle_input);	\
> diff --git a/lib/librte_eal/common/include/rte_common.h b/lib/librte_eal/common/include/rte_common.h
> index 8ac940c..40c2603 100644
> --- a/lib/librte_eal/common/include/rte_common.h
> +++ b/lib/librte_eal/common/include/rte_common.h
> @@ -43,6 +43,7 @@
> 
>  #ifdef __cplusplus
>  extern "C" {
> +
>  #endif
> 
>  #include <stdint.h>
> @@ -112,7 +113,7 @@ rte_align_floor_int(uintptr_t ptr, uintptr_t align)
>   * must be a power-of-two value.
>   */
>  #define RTE_PTR_ALIGN_FLOOR(ptr, align) \
> -	(typeof(ptr))rte_align_floor_int((uintptr_t)ptr, align)
> +	(__typeof__(ptr))rte_align_floor_int((uintptr_t)ptr, align)
> 
>  /**
>   * Macro to align a value to a given power-of-two. The resultant value
> @@ -121,7 +122,7 @@ rte_align_floor_int(uintptr_t ptr, uintptr_t align)
>   * power-of-two value.
>   */
>  #define RTE_ALIGN_FLOOR(val, align) \
> -	(typeof(val))((val) & (~((typeof(val))((align) - 1))))
> +	(__typeof__(val))((val) & (~((__typeof__(val))((align) - 1))))
> 
>  /**
>   * Macro to align a pointer to a given power-of-two. The resultant
> @@ -130,7 +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((typeof(ptr))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
> @@ -139,7 +140,7 @@ rte_align_floor_int(uintptr_t ptr, uintptr_t align)
>   * value.
>   */
>  #define RTE_ALIGN_CEIL(val, align) \
> -	RTE_ALIGN_FLOOR(((val) + ((typeof(val)) (align) - 1)), align)
> +	RTE_ALIGN_FLOOR(((val) + ((__typeof__(val)) (align) - 1)), align)
> 
>  /**
>   * Macro to align a pointer to a given power-of-two. The resultant
> @@ -257,8 +258,8 @@ rte_align64pow2(uint64_t v)
>   * Macro to return the minimum of two numbers
>   */
>  #define RTE_MIN(a, b) ({ \
> -		typeof (a) _a = (a); \
> -		typeof (b) _b = (b); \
> +		__typeof__ (a) _a = (a); \
> +		__typeof__ (b) _b = (b); \
>  		_a < _b ? _a : _b; \
>  	})
> 
> @@ -266,8 +267,8 @@ rte_align64pow2(uint64_t v)
>   * Macro to return the maximum of two numbers
>   */
>  #define RTE_MAX(a, b) ({ \
> -		typeof (a) _a = (a); \
> -		typeof (b) _b = (b); \
> +		__typeof__ (a) _a = (a); \
> +		__typeof__ (b) _b = (b); \
>  		_a > _b ? _a : _b; \
>  	})
> 
> diff --git a/lib/librte_eal/common/include/rte_pci.h b/lib/librte_eal/common/include/rte_pci.h
> index 3df07e8..bc065d4 100644
> --- a/lib/librte_eal/common/include/rte_pci.h
> +++ b/lib/librte_eal/common/include/rte_pci.h
> @@ -212,7 +212,7 @@ do {                                                               \
>  	val = strtoul((in), &end, 16);                          \
>  	if (errno != 0 || end[0] != (dlm) || val > (lim))       \
>  		return (-EINVAL);                               \
> -	(fd) = (typeof (fd))val;                                \
> +	(fd) = (__typeof__ (fd))val;                            \
>  	(in) = end + 1;                                         \
>  } while(0)
> 
> --

Actually, I wonder wouldn't something like the one below be sufficient?
Konstantin

diff --git a/lib/librte_eal/common/include/rte_common.h b/lib/librte_eal/common/
index 8ac940c..1867692 100644
--- a/lib/librte_eal/common/include/rte_common.h
+++ b/lib/librte_eal/common/include/rte_common.h
@@ -51,6 +51,15 @@ extern "C" {
 #include <errno.h>
 #include <limits.h>

+#ifndef typeof
+#define typeof __typeof__
+#endif
+
+#ifndef asm
+#define asm __asm__
+#endif
+
+
 /*********** Macros to eliminate unused variable warnings ********/

 /**