Messages in this thread | | | From | Richard Fitzgerald <> | Subject | [PATCH v2 0/2] Fix truncation warnings from building test_scanf.c | Date | Tue, 25 May 2021 13:20:10 +0100 |
| |
The kernel test robot is reporting truncation warnings when building lib/test_scanf.c:
1) lib/test_scanf.c:250:9: sparse: sparse: cast truncates bits from constant value (ffff0001 becomes 1) Reported on several lines.
2) include/linux/prandom.h:114:45: sparse: sparse: cast truncates bits from constant value (4f2e5357408c3c09 becomes 408c3c09)
(1) is caused by test_scanf.c using type_min() on an unsigned type. The truncation is expected but the use of type_min() on an unsigned is unnecessary because we know it is always 0.
(2) is caused by prandom_seed_state() storing a modified u64 seed value into a u32 - sparse will warn that this causes a truncation.
The two patches in this series fix these problems.
Richard Fitzgerald (2): lib: test_scanf: Remove pointless use of type_min() with unsigned types random32: Fix implicit truncation warning in prandom_seed_state()
include/linux/prandom.h | 2 +- lib/test_scanf.c | 13 ++++++------- 2 files changed, 7 insertions(+), 8 deletions(-)
-- 2.20.1
| |