When building with -Wsometimes-uninitialized, Clang warns: arch/x86/kernel/hw_breakpoint.c:355:2: warning: variable 'align' is used uninitialized whenever switch default is taken [-Wsometimes-uninitialized]
It's not wrong but we can see that arch_build_bp_info will only ever initialize hw->len to one of the specified switch cases. We can easily silence Clang by just returning -EINVAL in the default case so that we can never use align without initializing it first. Link: https://github.com/ClangBuiltLinux/linux/issues/392 Suggested-by: Nick Desaulniers <ndesaulni...@google.com> Signed-off-by: Nathan Chancellor <natechancel...@gmail.com> --- arch/x86/kernel/hw_breakpoint.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/kernel/hw_breakpoint.c b/arch/x86/kernel/hw_breakpoint.c index ff9bfd40429e..d73083021002 100644 --- a/arch/x86/kernel/hw_breakpoint.c +++ b/arch/x86/kernel/hw_breakpoint.c @@ -354,6 +354,7 @@ int hw_breakpoint_arch_parse(struct perf_event *bp, #endif default: WARN_ON_ONCE(1); + return -EINVAL; } /* -- 2.21.0
