Patch "Kbuild: disable 'maybe-uninitialized' warning for CONFIG_PROFILE_ALL_BRANCHES" has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

Kbuild: disable 'maybe-uninitialized' warning for CONFIG_PROFILE_ALL_BRANCHES

to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
kbuild-disable-maybe-uninitialized-warning-for-config_profile_all_branches.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Arnd Bergmann <[email protected]>
Date: Mon, 25 Apr 2016 17:35:28 +0200
Subject: Kbuild: disable 'maybe-uninitialized' warning for CONFIG_PROFILE_ALL_BRANCHES

From: Arnd Bergmann <[email protected]>

commit 815eb71e7149ecce40db9dd0ad09c4dd9d33c60f upstream.

CONFIG_PROFILE_ALL_BRANCHES confuses gcc-5.x to the degree that it prints incorrect warnings about a lot of variables that it thinks can be used uninitialized, e.g.:

i2c/busses/i2c-diolan-u2c.c: In function 'diolan_usb_xfer':
i2c/busses/i2c-diolan-u2c.c:391:16: warning: 'byte' may be used uninitialized in this function iio/gyro/itg3200_core.c: In function 'itg3200_probe':
iio/gyro/itg3200_core.c:213:6: warning: 'val' may be used uninitialized in this function leds/leds-lp55xx-common.c: In function 'lp55xx_update_bits':
leds/leds-lp55xx-common.c:350:6: warning: 'tmp' may be used uninitialized in this function misc/bmp085.c: In function 'show_pressure':
misc/bmp085.c:363:10: warning: 'pressure' may be used uninitialized in this function power/ds2782_battery.c: In function 'ds2786_get_capacity':
power/ds2782_battery.c:214:17: warning: 'raw' may be used uninitialized in this function

These are all false positives that either rob someone's time when trying to figure out whether they are real, or they get people to send wrong patches to shut up the warnings.

Nobody normally wants to run a CONFIG_PROFILE_ALL_BRANCHES kernel in production, so disabling the whole class of warnings for this configuration has no serious downsides either.

---
 Makefile |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

@@ -620,7 +620,11 @@ KBUILD_CFLAGS	+= $(call cc-option,-fno-d
 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
 KBUILD_CFLAGS	+= -Os $(call cc-disable-warning,maybe-uninitialized,)
 else
-KBUILD_CFLAGS	+= -O2
+ifdef CONFIG_PROFILE_ALL_BRANCHES
+KBUILD_CFLAGS	+= -O2 $(call cc-disable-warning,maybe-uninitialized,)
+else
+KBUILD_CFLAGS   += -O2
+endif
 endif
 
 # Tell gcc to never replace conditional load with a non-conditional one

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/include-linux-kernel.h-change-abs-macro-so-it-uses-consistent-return-type.patch queue-4.4/ath9k-fix-misleading-indentation.patch queue-4.4/iwlegacy-avoid-warning-about-missing-braces.patch queue-4.4/kbuild-disable-maybe-uninitialized-warning-for-config_profile_all_branches.patch queue-4.4/net-caif-fix-misleading-indentation.patch queue-4.4/nouveau-fix-nv40_perfctr_next-cleanup-regression.patch queue-4.4/gcov-disable-wmaybe-uninitialized-warning.patch queue-4.4/am437x-vfpe-fix-typo-in-vpfe_get_app_input_index.patch queue-4.4/fix-build-warning-in-kernel-cpuset.c.patch queue-4.4/reiserfs-fix-new_insert_key-may-be-used-uninitialized.patch