Re: [dpdk-dev] [PATCH v5 14/26] common/mlx5: add list lcore share

[Suanming Mou <suanmingm@nvidia.com>]

Hi Raslan,

> -----Original Message-----
> From: Raslan Darawsheh <rasland@nvidia.com>
> Sent: Monday, July 12, 2021 10:59 PM
> To: Suanming Mou <suanmingm@nvidia.com>; Slava Ovsiienko
> <viacheslavo@nvidia.com>; Matan Azrad <matan@nvidia.com>
> Cc: Ori Kam <orika@nvidia.com>; dev@dpdk.org
> Subject: RE: [PATCH v5 14/26] common/mlx5: add list lcore share
> 
> Hi Suanming,
> 
> This patch will cause the following failure in compilation with CLANG :
> [1443/3183] Compiling C object
> drivers/libtmp_rte_common_mlx5.a.p/common_mlx5_mlx5_common_utils.c.o
> FAILED:
> drivers/libtmp_rte_common_mlx5.a.p/common_mlx5_mlx5_common_utils.c.o
> clang -Idrivers/libtmp_rte_common_mlx5.a.p -Idrivers -I../../root/dpdk/drivers -
> Idrivers/common/mlx5 -I../../root/dpdk/drivers/common/mlx5 -
> Idrivers/common/mlx5/linux -I../../root/dpdk/drivers/common/mlx5/linux -
> Ilib/hash -I../../root/dpdk/lib/hash -I. -I../../root/dpdk -Iconfig -
> I../../root/dpdk/config -Ilib/eal/include -I../../root/dpdk/lib/eal/include -
> Ilib/eal/linux/include -I../../root/dpdk/lib/eal/linux/include -Ilib/eal/x86/include
> -I../../root/dpdk/lib/eal/x86/include -Ilib/eal/common -
> I../../root/dpdk/lib/eal/common -Ilib/eal -I../../root/dpdk/lib/eal -Ilib/kvargs -
> I../../root/dpdk/lib/kvargs -Ilib/metrics -I../../root/dpdk/lib/metrics -
> Ilib/telemetry -I../../root/dpdk/lib/telemetry -Ilib/net -I../../root/dpdk/lib/net -
> Ilib/mbuf -I../../root/dpdk/lib/mbuf -Ilib/mempool -
> I../../root/dpdk/lib/mempool -Ilib/ring -I../../root/dpdk/lib/ring -Ilib/rcu -
> I../../root/dpdk/lib/rcu -Ilib/pci -I../../root/dpdk/lib/pci -Idrivers/bus/pci -
> I../../root/dpdk/drivers/bus/pci -I../../root/dpdk/drivers/bus/pci/linux -
> I/usr/usr/include -Xclang -fcolor-diagnostics -pipe -D_FILE_OFFSET_BITS=64 -
> Wall -Winvalid-pch -Werror -O2 -g -include rte_config.h -Wextra -Wcast-qual -
> Wdeprecated -Wformat -Wformat-nonliteral -Wformat-security -Wmissing-
> declarations -Wmissing-prototypes -Wnested-externs -Wold-style-definition -
> Wpointer-arith -Wsign-compare -Wstrict-prototypes -Wundef -Wwrite-strings -
> Wno-address-of-packed-member -Wno-missing-field-initializers -
> D_GNU_SOURCE -fPIC -march=native -DALLOW_EXPERIMENTAL_API -
> DALLOW_INTERNAL_API -std=c11 -Wno-strict-prototypes -D_BSD_SOURCE -
> D_DEFAULT_SOURCE -D_XOPEN_SOURCE=600 -pedantic -DPEDANTIC -
> DRTE_LOG_DEFAULT_LOGTYPE=pmd.common.mlx5 -MD -MQ
> drivers/libtmp_rte_common_mlx5.a.p/common_mlx5_mlx5_common_utils.c.o
> -MF
> drivers/libtmp_rte_common_mlx5.a.p/common_mlx5_mlx5_common_utils.c.o.
> d -o
> drivers/libtmp_rte_common_mlx5.a.p/common_mlx5_mlx5_common_utils.c.o
> -c ../../root/dpdk/drivers/common/mlx5/mlx5_common_utils.c
> ../../root/dpdk/drivers/common/mlx5/mlx5_common_utils.c:152:6: error:
> variable 'entry' is used uninitialized whenever 'if' condition is false [-Werror,-
> Wsometimes-uninitialized]
>         if (list->lcores_share) {
>             ^~~~~~~~~~~~~~~~~~
> ../../root/dpdk/drivers/common/mlx5/mlx5_common_utils.c:165:32: note:
> uninitialized use occurs here
>         entry = list->cb_create(list, entry, ctx);
>                                       ^~~~~
> ../../root/dpdk/drivers/common/mlx5/mlx5_common_utils.c:152:2: note:
> remove the 'if' if its condition is always true
>         if (list->lcores_share) {
>         ^~~~~~~~~~~~~~~~~~~~~~~~
> ../../root/dpdk/drivers/common/mlx5/mlx5_common_utils.c:136:31: note:
> initialize the variable 'entry' to silence this warning
>         struct mlx5_list_entry *entry, *local_entry;
>                                      ^
>                                       = NULL
> 1 error generated.
> [1500/3183] Compiling C object
> drivers/libtmp_rte_net_mlx5.a.p/net_mlx5_mlx5_tx_empw.c.o
> ninja: build stopped: subcommand failed.
> 
> 
> ########################
> Build failed!
>         CC: clang version 12.0.0 (Fedora 12.0.0-2.fc34)

OK, I will check it.

> 
> 
> Kindest regards,
> Raslan Darawsheh
>