• Arnd Bergmann's avatar
    kbuild: move -Wunused-const-variable to W=1 warning level · c9c6837d
    Arnd Bergmann authored
    gcc-6 started warning by default about variables that are not
    used anywhere and that are marked 'const', generating many
    false positives in an allmodconfig build, e.g.:
    
    arch/arm/mach-davinci/board-da830-evm.c:282:20: warning: 'da830_evm_emif25_pins' defined but not used [-Wunused-const-variable=]
    arch/arm/plat-omap/dmtimer.c:958:34: warning: 'omap_timer_match' defined but not used [-Wunused-const-variable=]
    drivers/bluetooth/hci_bcm.c:625:39: warning: 'acpi_bcm_default_gpios' defined but not used [-Wunused-const-variable=]
    drivers/char/hw_random/omap-rng.c:92:18: warning: 'reg_map_omap4' defined but not used [-Wunused-const-variable=]
    drivers/devfreq/exynos/exynos5_bus.c:381:32: warning: 'exynos5_busfreq_int_pm' defined but not used [-Wunused-const-variable=]
    drivers/dma/mv_xor.c:1139:34: warning: 'mv_xor_dt_ids' defined but not used [-Wunused-const-variable=]
    
    This is similar to the existing -Wunused-but-set-variable warning
    that was added in an earlier release and that we disable by default
    now and only enable when W=1 is set, so it makes sense to do
    the same here. Once we have eliminated the majority of the
    warnings for both, we can put them back into the default list.
    
    We probably want this in backport kernels as well, to allow building
    them with gcc-6 without introducing extra warnings.
    Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
    Acked-by: default avatarOlof Johansson <olof@lixom.net>
    Acked-by: default avatarLee Jones <lee.jones@linaro.org>
    Cc: stable@vger.kernel.org
    Signed-off-by: default avatarMichal Marek <mmarek@suse.com>
    c9c6837d
Makefile 56 KB