[Linux-stm32] [PATCH] net: stmmac: Avoid one more sometimes uninitialized Clang warning

[David Miller]

From: Nathan Chancellor <natechancellor at gmail.com>
Date: Thu,  7 Mar 2019 21:02:39 -0700

> When building with -Wsometimes-uninitialized, Clang warns:
> 
> drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c:111:2: error: variable
> 'ns' is used uninitialized whenever 'if' condition is false
> [-Werror,-Wsometimes-uninitialized]
> drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c:111:2: error: variable
> 'ns' is used uninitialized whenever '&&' condition is false
> [-Werror,-Wsometimes-uninitialized]
> 
> Clang is concerned with the use of stmmac_do_void_callback (which
> stmmac_get_systime wraps), as it may fail to initialize these values if
> the if condition was ever false (meaning the callback doesn't exist).
> It's not wrong because the callback is what initializes ns. While it's
> unlikely that the callback is going to disappear at some point and make
> that condition false, we can easily avoid this warning by zero
> initializing the variable.
> 
> Link: https://github.com/ClangBuiltLinux/linux/issues/384
> Fixes: df103170854e ("net: stmmac: Avoid sometimes uninitialized Clang warnings")
> Suggested-by: Nick Desaulniers <ndesaulniers at google.com>
> Signed-off-by: Nathan Chancellor <natechancellor at gmail.com>

Applied, thanks Nathan.