From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann To: Cyrille Pitchen , Marek Vasut Cc: Arnd Bergmann , David Woodhouse , Brian Norris , Boris Brezillon , Richard Weinberger , Maxime Coquelin , Alexandre Torgue , Ludovic Barre , linux-mtd@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH] mtd: spi-nor: stm32-quadspi: avoid unintialized return code Date: Thu, 14 Sep 2017 13:06:59 +0200 Message-Id: <20170914110709.3591691-1-arnd@arndb.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , If we send zero-length data to stm32_qspi_tx_poll() on older compiler versions such as gcc-4.6, we get warned that the return code is uninitialized: drivers/mtd/spi-nor/stm32-quadspi.c:248:2: error: ‘ret’ may be used uninitialized in this function [-Werror=uninitialized] On newer compiler versions, the return code is always zero in this case, as the local variable gets optimized away and is assumed to be zero after the loop completes without error. This changes the function to instead return -EINVAL if it ever gets called with a zero length buffer. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82203 Signed-off-by: Arnd Bergmann --- drivers/mtd/spi-nor/stm32-quadspi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/mtd/spi-nor/stm32-quadspi.c b/drivers/mtd/spi-nor/stm32-quadspi.c index 86c0931543c5..711cfe7aa4bf 100644 --- a/drivers/mtd/spi-nor/stm32-quadspi.c +++ b/drivers/mtd/spi-nor/stm32-quadspi.c @@ -227,7 +227,7 @@ static int stm32_qspi_tx_poll(struct stm32_qspi *qspi, void (*tx_fifo)(u8 *, void __iomem *); u32 len = cmd->len, sr; u8 *buf = cmd->buf; - int ret; + int ret = -EINVAL; if (cmd->qspimode == CCR_FMODE_INDW) tx_fifo = stm32_qspi_write_fifo; -- 2.9.0