… > +++ b/drivers/spi/spi.c … > +static int __spi_optimize_message(struct spi_device *spi, > + struct spi_message *msg) … I propose to reconsider the usage of leading underscores in such identifiers. See also: https://wiki.sei.cmu.edu/confluence/display/c/DCL37-C.+Do+not+declare+or+define+a+reserved+identifier Regards, Markus