[PATCH 8/9] net: nb8800: avoid uninitialized variable warning
From: Måns Rullgård <hidden>
Date: 2016-01-27 14:13:30
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lkml, netdev
Arnd Bergmann [off-list ref] writes:
The nb8800_poll() function initializes the 'next' variable in the loop looking for new input data. We know this will be called at least once because 'budget' is a guaranteed to be a positive number when we enter the function, but the compiler doesn't know that and warns when the variable is used later: drivers/net/ethernet/aurora/nb8800.c: In function 'nb8800_poll': drivers/net/ethernet/aurora/nb8800.c:350:21: warning: 'next' may be used uninitialized in this function [-Wmaybe-uninitialized]
Which gcc version is this? 4.9 doesn't warn here, presumably because it's clever enough to notice that the offending use of 'next' is under a condition that can only be true if the first one was. Of course fixing the code so older compilers don't warn is a good idea.
Changing the 'while() {}' loop to 'do {} while()' makes it obvious
to the compiler what is going on so it no longer warns.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>Acked-by: Mans Rullgard <redacted>
quoted hunk
--- drivers/net/ethernet/aurora/nb8800.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)diff --git a/drivers/net/ethernet/aurora/nb8800.c b/drivers/net/ethernet/aurora/nb8800.c index ecc4a334c507..f71ab2647a3b 100644 --- a/drivers/net/ethernet/aurora/nb8800.c +++ b/drivers/net/ethernet/aurora/nb8800.c@@ -302,7 +302,7 @@ static int nb8800_poll(struct napi_struct *napi, int budget) nb8800_tx_done(dev); again: - while (work < budget) { + do { struct nb8800_rx_buf *rxb; unsigned int len;@@ -330,7 +330,7 @@ again: rxd->report = 0; last = next; work++; - } + } while (work < budget); if (work) { priv->rx_descs[last].desc.config |= DESC_EOC;-- 2.7.0
-- M?ns Rullg?rd