On Sat, Feb 01, 2014 at 10:43:11AM -0800, Linus Torvalds wrote: > On Fri, Jan 31, 2014 at 6:32 AM, Greg KH <gre...@linuxfoundation.org> wrote: > > > > Here's a single staging driver for a wireless chipset that has shown up > > in the SteamBox hardware. It is merged separately from the "main" > > staging pull request to sync up with the wireless api changes that came > > in from the networking tree. > > It causes an interesting warning for me: > > drivers/staging/rtl8821ae/rtl8821ae/dm.c: In function > ‘rtl8821ae_dm_clear_txpower_tracking_state’: > drivers/staging/rtl8821ae/rtl8821ae/dm.c:487:31: warning: iteration 2u > invokes undefined behavior [-Waggressive-loop-optimizations] > rtldm->bb_swing_idx_ofdm[p] = rtldm->default_ofdm_index; > ^ > drivers/staging/rtl8821ae/rtl8821ae/dm.c:485:2: note: containing loop > for (p = RF90_PATH_A; p < MAX_RF_PATH; ++p) { > ^ > > and gcc is entirely correct: that loop iterates from 0 to 3, and does this: > > rtldm->bb_swing_idx_ofdm[p] = rtldm->default_ofdm_index; > > but the bb_swing_idx_ofdm[] array only has two members. So the last > two iterations will overwrite bb_swing_idx_ofdm_current and the first > entry in bb_swing_idx_ofdm_base[]. > > Now, the bug does seem to be benign: bb_swing_idx_ofdm_current isn't > actually ever *used* as far as I can tell, and the first entry of > bb_swing_idx_ofdm_base[] will have been written with that same > "rtldm->default_ofdm_index" value. > > But gcc is absolutely correct, and that driver needs fixing. > > I've pulled it and will let it be because it doesn't seem to be an > issue in practice, but please fix it. The obvious fix would seem to > change the size of "2" to be "MAX_RF_PATH", but I'll abstain from > doing those kinds of changes in the merge when it doesn't seem to > affect the build or functionality).
Ok, thanks, someone's already sent me that patch to fix this up, I'll queue it up for the post-rc1 set of staging tree fixes. greg k-h _______________________________________________ devel mailing list de...@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel