Re: [dpdk-dev] [PATCH v2 04/10] event/octeontx2: fix maybe-uninitialized warnings for LTO build

Re: [dpdk-dev] [PATCH v2 04/10] event/octeontx2: fix maybe-uninitialized warnings for LTO build

[Pavan Nikhilesh Bhagavatula]

>During LTO build compiler reports some 'false positive' warnings about
>variables being possibly used uninitialized.  This patch silences these
>warnings.
>
>Signed-off-by: Andrzej Ostruszka <aostruszka@marvell.com>

Acked-by: Pavan Nikhilesh <pbhagavatula@marvell.com>

>---
> drivers/event/octeontx2/otx2_tim_worker.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
>diff --git a/drivers/event/octeontx2/otx2_tim_worker.h
>b/drivers/event/octeontx2/otx2_tim_worker.h
>index b193e2cab..50db6543c 100644
>--- a/drivers/event/octeontx2/otx2_tim_worker.h
>+++ b/drivers/event/octeontx2/otx2_tim_worker.h
>@@ -337,7 +337,7 @@ tim_add_entry_brst(struct otx2_tim_ring *
>const tim_ring,
> 		   const struct otx2_tim_ent *ents,
> 		   const uint16_t nb_timers, const uint8_t flags)
> {
>-	struct otx2_tim_ent *chunk;
>+	struct otx2_tim_ent *chunk = NULL;
> 	struct otx2_tim_bkt *bkt;
> 	uint16_t chunk_remainder;
> 	uint16_t index = 0;
>--
>2.17.1

[dpdk-dev] [PATCH v2 00/10] Add an option to use LTO for DPDK build

[Andrzej Ostruszka]

This patch series adds an option to make use of link time optimization
(if compiler has support for it).  It is split as follows:
- 1st patch (build) is the enablement
- remaining patches are fixes for the warnings produced by the compiler
  and they are split by directory/subsystem so their maintainers can
  easily find and verify the changes - please note that there are two
  groups:
  * errors (or possible errors) - with title "fix possible use ..."
  * false positives - warnings that _I_ think are not valid and the
    changes are made only to silence the compiler.

v2 Changes:
-----------
- fixed building of shared libraries:
  - gcc does not scan top level assembler statements so it missed that
    function implementations for specific versions were being used and
    was removing them
- fixed meson.build config files:
  - moved from 'enable_lto' project option to built-in 'b_lto'
  - documented that 'default_library' should be 'shared':
    with 'default_library=static' (the default) the meson build with LTO
    is broken - this is because, SHARED_LIB is fixed in rte_config.h
    used by meson which leads to no alias for default version in
    generated static libraries (MAP_STATIC_SYMBOL() is empty)
- app/test: added log for failed bonding "config get"

Andrzej Ostruszka (10):
  build: add an option to enable LTO build
  eventdev: fix possible use of uninitialized var
  app/eventdev: fix maybe-uninitialized warnings for LTO build
  event/octeontx2: fix maybe-uninitialized warnings for LTO build
  app/test: fix maybe-uninitialized warnings for LTO build
  net/dpaa2: fix possible use of uninitialized vars
  net/e1000: fix maybe-uninitialized warnings for LTO build
  net/i40e: fix maybe-uninitialized warnings for LTO build
  net/ifc: fix maybe-uninitialized warnings for LTO build
  net/qede: fix maybe-uninitialized warnings for LTO build

 .travis.yml                                   |  7 ++++
 app/test-eventdev/test_perf_common.c          |  2 +-
 app/test-eventdev/test_pipeline_common.c      |  4 +-
 app/test/test_hash_readwrite.c                |  2 +-
 app/test/test_link_bonding_mode4.c            | 10 ++++-
 app/test/test_memzone.c                       |  3 +-
 config/common_base                            |  5 +++
 config/meson.build                            | 15 ++++++++
 doc/guides/prog_guide/lto.rst                 | 37 +++++++++++++++++++
 doc/guides/rel_notes/release_19_11.rst        |  8 ++++
 drivers/event/octeontx2/otx2_tim_worker.h     |  2 +-
 drivers/net/dpaa2/base/dpaa2_hw_dpni.c        |  1 +
 drivers/net/dpaa2/mc/dpkg.c                   |  2 +-
 drivers/net/dpaa2/mc/dpni.c                   |  9 +++--
 drivers/net/e1000/base/e1000_82543.c          |  2 +-
 drivers/net/e1000/base/e1000_ich8lan.c        |  2 +-
 drivers/net/e1000/base/e1000_phy.c            |  2 +-
 drivers/net/i40e/i40e_ethdev.c                |  2 +-
 drivers/net/ifc/ifcvf_vdpa.c                  | 14 ++++---
 drivers/net/qede/base/ecore_mcp.c             | 13 ++++---
 lib/librte_distributor/rte_distributor.c      | 18 ++++-----
 lib/librte_distributor/rte_distributor_v20.c  | 18 ++++-----
 lib/librte_eventdev/rte_event_timer_adapter.c |  8 ++--
 lib/librte_lpm/rte_lpm.c                      | 28 +++++++-------
 lib/librte_lpm/rte_lpm6.c                     | 16 ++++----
 lib/librte_timer/rte_timer.c                  | 20 +++++-----
 mk/toolchain/clang/rte.toolchain-compat.mk    |  4 ++
 mk/toolchain/clang/rte.vars.mk                |  8 ++++
 mk/toolchain/gcc/rte.toolchain-compat.mk      |  4 ++
 mk/toolchain/gcc/rte.vars.mk                  | 12 ++++++
 mk/toolchain/icc/rte.vars.mk                  |  8 ++++
 31 files changed, 205 insertions(+), 81 deletions(-)
 create mode 100644 doc/guides/prog_guide/lto.rst

-- 
2.17.1

[dpdk-dev] [PATCH v2 04/10] event/octeontx2: fix maybe-uninitialized warnings for LTO build

[Andrzej Ostruszka]

During LTO build compiler reports some 'false positive' warnings about
variables being possibly used uninitialized.  This patch silences these
warnings.

Signed-off-by: Andrzej Ostruszka <aostruszka@marvell.com>
---
 drivers/event/octeontx2/otx2_tim_worker.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/event/octeontx2/otx2_tim_worker.h b/drivers/event/octeontx2/otx2_tim_worker.h
index b193e2cab..50db6543c 100644
--- a/drivers/event/octeontx2/otx2_tim_worker.h
+++ b/drivers/event/octeontx2/otx2_tim_worker.h
@@ -337,7 +337,7 @@ tim_add_entry_brst(struct otx2_tim_ring * const tim_ring,
 		   const struct otx2_tim_ent *ents,
 		   const uint16_t nb_timers, const uint8_t flags)
 {
-	struct otx2_tim_ent *chunk;
+	struct otx2_tim_ent *chunk = NULL;
 	struct otx2_tim_bkt *bkt;
 	uint16_t chunk_remainder;
 	uint16_t index = 0;
-- 
2.17.1