Re: [dpdk-dev] [EXT] [PATCH v5] crypto/qat: fix uninitialized gcc compiler warning

[Akhil Goyal <gakhil@marvell.com>]

> In Arm platform, when "RTE_ARCH_ARM64_MEMCPY" is set as true, gcc will
> report variable uninitialized warning:
> 
> ../drivers/crypto/qat/qat_sym_session.c: In function
> ‘partial_hash_compute’:
> ../lib/eal/include/generic/rte_byteorder.h:241:24: warning:
> ‘<U35a0>’ may be used uninitialized in this function
> 	[-Wmaybe-uninitialized]
> 	241 | #define rte_bswap32(x) __builtin_bswap32(x)
> 	...
> 
> This is because "digest" will be initialized by "rte_memcpy" function
> rather than "memcpy" if "RTE_ARCH_ARM64_MEMCPY" is set as true.
> Furthermore, 'rte_memcpy' will initialize 'digest' with two steps
> by invoking rte_mov_x functions. For example:
> 
> partial_hash_sha1 -> rte_memcpy -> rte_memcpy_ge16_lt_128 ->
> step 1: rte_mov16(dst,src )
> step 2: rte_mov16(dst - 16 + n, src - 16 + n)
> 
> However, gcc compiler cannot identify this multi-step initialization,
> then it will report warning.
> 
> To fix this, use "memset" to initialize "digest".
> 
> Fixes: cd7fc8a84b48 ("eal/arm64: optimize memcpy")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Feifei Wang <feifei.wang2@arm.com>
> Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
> Reviewed-by: Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>
> Acked-by: Adam Dybkowski <adamx.dybkowski@intel.com>
> ---
> v2: add check and free for memory dynamic allocation (David Marchand)
> v3: fix compiler error
> v4: use 'memset' to initialize digest (Ferruh, Adam)
> v5: fixed spelling errors in commit message (Honnappa)
> 
Applied to dpdk-next-crypto

Thanks.