Re: [dpdk-dev] [PATCH] fm10k: fix the compilation on big endian platforms

[Thomas Monjalon <thomas.monjalon@6wind.com>]

2015-08-03 14:31, Chao Zhu:
> The rte_cpu_to_le_32 function can't be used to define const variables
> because it has different implementation on big endian platforms. If
> doing so, it will cause 'initializer element is not constant' compiling
> error. This patch fixes this problem.

> --- a/drivers/net/fm10k/base/fm10k_tlv.c
> +++ b/drivers/net/fm10k/base/fm10k_tlv.c

You cannot change a base driver file except the osdep header where
FM10K_CPU_TO_LE32 is defined.

I don't understand why it doesn't give you a constant, given this definition:

#define rte_bswap32(x) ((uint32_t)(__builtin_constant_p(x) ?        \                                            
                   rte_constant_bswap32(x) :        \
                   rte_arch_bswap32(x)))

Have you tried CONFIG_RTE_FORCE_INTRINSICS=y ?
It should trigger this definition:

#define rte_bswap32(x) __builtin_bswap32(x)

> -STATIC const __le32 test_le[2] = { FM10K_CPU_TO_LE32(0x12345678),
> -				   FM10K_CPU_TO_LE32(0x9abcdef0)};
> +#if RTE_BYTE_ORDER == RTE_BIG_ENDIAN
> +STATIC const __le32 test_le[2] = {0x78563412,0xf0debc9a};
> +#else
> +STATIC const __le32 test_le[2] = {0x12345678,0x9abcdef0};
> +#endif