staging: rtl8821ae: Fixed the size of array to macro as discussed by Linus
Linus Torvalds writes: 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). Reported-By: NLinus Torvalds <torvalds@linux-foundation.org> Signed-off-by: NSurendra Patil <surendra.tux@gmail.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
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