From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org,
Linus Torvalds <torvalds@linux-foundation.org>
Subject: [PATCH 4.7 10/69] Disable "maybe-uninitialized" warning globally
Date: Wed, 28 Sep 2016 11:04:52 +0200 [thread overview]
Message-ID: <20160928090445.494613870@linuxfoundation.org> (raw)
In-Reply-To: <20160928090445.054716307@linuxfoundation.org>
4.7-stable review patch. If anyone has any objections, please let me know.
------------------
From: Linus Torvalds <torvalds@linux-foundation.org>
commit 6e8d666e925333c55378e8d5540a8a9ee0eea9c5 upstream.
Several build configurations had already disabled this warning because
it generates a lot of false positives. But some had not, and it was
still enabled for "allmodconfig" builds, for example.
Looking at the warnings produced, every single one I looked at was a
false positive, and the warnings are frequent enough (and big enough)
that they can easily hide real problems that you don't notice in the
noise generated by -Wmaybe-uninitialized.
The warning is good in theory, but this is a classic case of a warning
that causes more problems than the warning can solve.
If gcc gets better at avoiding false positives, we may be able to
re-enable this warning. But as is, we're better off without it, and I
want to be able to see the *real* warnings.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
Makefile | 7 ++++---
arch/arc/Makefile | 4 +---
scripts/Makefile.ubsan | 4 ----
3 files changed, 5 insertions(+), 10 deletions(-)
--- a/Makefile
+++ b/Makefile
@@ -370,7 +370,7 @@ LDFLAGS_MODULE =
CFLAGS_KERNEL =
AFLAGS_KERNEL =
LDFLAGS_vmlinux =
-CFLAGS_GCOV = -fprofile-arcs -ftest-coverage -fno-tree-loop-im -Wno-maybe-uninitialized
+CFLAGS_GCOV = -fprofile-arcs -ftest-coverage -fno-tree-loop-im
CFLAGS_KCOV = -fsanitize-coverage=trace-pc
@@ -619,12 +619,13 @@ ARCH_CFLAGS :=
include arch/$(SRCARCH)/Makefile
KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
+KBUILD_CFLAGS += $(call cc-disable-warning,maybe-uninitialized,)
ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
-KBUILD_CFLAGS += -Os $(call cc-disable-warning,maybe-uninitialized,)
+KBUILD_CFLAGS += -Os
else
ifdef CONFIG_PROFILE_ALL_BRANCHES
-KBUILD_CFLAGS += -O2 $(call cc-disable-warning,maybe-uninitialized,)
+KBUILD_CFLAGS += -O2
else
KBUILD_CFLAGS += -O2
endif
--- a/arch/arc/Makefile
+++ b/arch/arc/Makefile
@@ -74,9 +74,7 @@ endif
ifndef CONFIG_CC_OPTIMIZE_FOR_SIZE
# Generic build system uses -O2, we want -O3
# Note: No need to add to cflags-y as that happens anyways
-#
-# Disable the false maybe-uninitialized warings gcc spits out at -O3
-ARCH_CFLAGS += -O3 $(call cc-disable-warning,maybe-uninitialized,)
+ARCH_CFLAGS += -O3
endif
# small data is default for elf32 tool-chain. If not usable, disable it
--- a/scripts/Makefile.ubsan
+++ b/scripts/Makefile.ubsan
@@ -14,8 +14,4 @@ ifdef CONFIG_UBSAN
ifdef CONFIG_UBSAN_ALIGNMENT
CFLAGS_UBSAN += $(call cc-option, -fsanitize=alignment)
endif
-
- # -fsanitize=* options makes GCC less smart than usual and
- # increase number of 'maybe-uninitialized false-positives
- CFLAGS_UBSAN += $(call cc-option, -Wno-maybe-uninitialized)
endif
next prev parent reply other threads:[~2016-09-28 9:04 UTC|newest]
Thread overview: 74+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20160928090645uscas1p25d8333ed85efe1cdd54dcaecedfc3b84@uscas1p2.samsung.com>
2016-09-28 9:04 ` [PATCH 4.7 00/69] 4.7.6-stable review Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.7 01/69] reiserfs: fix "new_insert_key may be used uninitialized ..." Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.7 02/69] crypto: arm64/aes-ctr - fix NULL dereference in tail processing Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.7 03/69] crypto: arm/aes-ctr " Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.7 04/69] crypto: skcipher - Fix blkcipher walk OOM crash Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.7 05/69] crypto: echainiv - Replace chaining with multiplication Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.7 06/69] ocfs2/dlm: fix race between convert and migration Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.7 07/69] ocfs2: fix start offset to ocfs2_zero_range_for_truncate() Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.7 08/69] Revert "ocfs2: bump up o2cb network protocol version" Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.7 09/69] autofs: use dentry flags to block walks during expire Greg Kroah-Hartman
2016-09-28 9:04 ` Greg Kroah-Hartman [this message]
2016-09-28 9:04 ` [PATCH 4.7 12/69] Makefile: Mute warning for __builtin_return_address(>0) for tracing only Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.7 13/69] xfs: prevent dropping ioend completions during buftarg wait Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.7 14/69] mm: fix the page_swap_info() BUG_ON check Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.7 15/69] fsnotify: add a way to stop queueing events on group shutdown Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.7 16/69] fanotify: fix list corruption in fanotify_get_response() Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.7 17/69] mm: memcontrol: make per-cpu charge cache IRQ-safe for socket accounting Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 18/69] cgroup: duplicate cgroup reference when cloning sockets Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 19/69] fix fault_in_multipages_...() on architectures with no-op access_ok() Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 20/69] KEYS: Fix skcipher IV clobbering Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 21/69] arm64: Call numa_store_cpu_info() earlier Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 22/69] configfs: Return -EFBIG from configfs_write_bin_file Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 24/69] mtd: maps: sa1100-flash: potential NULL dereference Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 25/69] mtd: pmcmsp-flash: Allocating too much in init_msp_flash() Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 26/69] mtd: spi-nor: fix wrong "fully unlocked" test Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 27/69] reset: Return -ENOTSUPP when not configured Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 28/69] rtc: ds1307: Fix relying on reset value for weekday Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 29/69] power: reset: hisi-reboot: Unmap region obtained by of_iomap Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 30/69] mac80211: reject TSPEC TIDs (TSIDs) for aggregation Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 31/69] fix memory leaks in tracing_buffers_splice_read() Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 32/69] tracing: Move mutex to protect against resetting of seq data Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 33/69] mm: delete unnecessary and unsafe init_tlb_ubc() Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 34/69] can: flexcan: fix resume function Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 35/69] net: can: ifi: Configure transmitter delay Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 36/69] iwlwifi: mvm: update TX queue before making a copy of the skb Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 37/69] nl80211: validate number of probe response CSA counters Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 38/69] btrfs: ensure that file descriptor used with subvol ioctls is a dir Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 39/69] x86/efi: Only map RAM into EFI page tables if in mixed-mode Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 40/69] irqchip/mips-gic: Fix local interrupts Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 41/69] i2c-eg20t: fix race between i2c init and interrupt enable Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 42/69] i2c: mux: pca954x: retry updating the mux selection on failure Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 43/69] i2c: qup: skip qup_i2c_suspend if the device is already runtime suspended Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 44/69] MIPS: Fix pre-r6 emulation FPU initialisation Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 45/69] MIPS: SMP: Fix possibility of deadlock when bringing CPUs online Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 46/69] MIPS: vDSO: Fix Malta EVA mapping to vDSO page structs Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 47/69] MIPS: Remove compact branch policy Kconfig entries Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 48/69] MIPS: Avoid a BUG warning during prctl(PR_SET_FP_MODE, ...) Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 49/69] MIPS: Add a missing ".set pop" in an early commit Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 50/69] MIPS: paravirt: Fix undefined reference to smp_bootstrap Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 51/69] x86/mm/pat: Prevent hang during boot when mapping pages Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 52/69] libceph: add an ONSTACK initializer for oids Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 53/69] ceph: fix symbol versioning for ceph_monc_do_statfs Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 54/69] ceph: Correctly return NXIO errors from ceph_llseek Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 55/69] libceph: fix return value check in alloc_msg_with_page_vector() Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 56/69] PM / hibernate: Restore processor state before using per-CPU variables Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 57/69] PM / hibernate: Fix rtree_next_node() to avoid walking off list ends Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 58/69] power_supply: tps65217-charger: fix missing platform_set_drvdata() Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 59/69] power: supply: max17042_battery: fix model download bug Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 60/69] ixgbe: Force VLNCTRL.VFE to be set in all VMDq paths Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 61/69] ixgbe: Re-enable ability to toggle VLAN filtering Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 62/69] igb: fix adjusting PTP timestamps for Tx/Rx latency Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 63/69] soc/tegra: pmc: Dont probe PMC if early initialisation fails Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 64/69] qxl: check for kmap failures Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 65/69] hostfs: Freeing an ERR_PTR in hostfs_fill_sb_common() Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 66/69] kasan: avoid overflowing quarantine size on low memory systems Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 67/69] mm/kasan: dont reduce quarantine in atomic contexts Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.7 68/69] iw_cxgb4: stop MPA_REPLY timer when disconnecting Greg Kroah-Hartman
2016-09-28 16:46 ` [PATCH 4.7 00/69] 4.7.6-stable review Shuah Khan
2016-09-29 9:00 ` Greg Kroah-Hartman
2016-09-28 22:44 ` Guenter Roeck
2016-09-29 9:00 ` Greg Kroah-Hartman
[not found] ` <57ec0654.4756c20a.c7ddf.48d1@mx.google.com>
[not found] ` <7ha8erru8h.fsf@baylibre.com>
2016-09-29 8:33 ` Greg Kroah-Hartman
2016-09-29 14:46 ` Kevin Hilman
2016-09-29 15:26 ` Greg Kroah-Hartman
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