From: Nathan Chancellor natechancellor@gmail.com
commit d422c6c0644bccbb1ebeefffa51f35cec3019517 upstream.
When building xway_defconfig with clang:
arch/mips/lantiq/prom.c:82:23: error: array comparison always evaluates to true [-Werror,-Wtautological-compare] else if (__dtb_start != __dtb_end) ^ 1 error generated.
These are not true arrays, they are linker defined symbols, which are just addresses. Using the address of operator silences the warning and does not change the resulting assembly with either clang/ld.lld or gcc/ld (tested with diff + objdump -Dr). Do the same thing across the entire MIPS subsystem to ensure there are no more warnings around this type of comparison.
Link: https://github.com/ClangBuiltLinux/linux/issues/1232 Signed-off-by: Nathan Chancellor natechancellor@gmail.com Acked-by: Florian Fainelli f.fainelli@gmail.com Signed-off-by: Thomas Bogendoerfer tsbogend@alpha.franken.de Cc: Sudip Mukherjee sudipm.mukherjee@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/mips/bmips/setup.c | 2 +- arch/mips/lantiq/prom.c | 2 +- arch/mips/pic32/pic32mzda/init.c | 2 +- arch/mips/ralink/of.c | 2 +- 4 files changed, 4 insertions(+), 4 deletions(-)
--- a/arch/mips/bmips/setup.c +++ b/arch/mips/bmips/setup.c @@ -167,7 +167,7 @@ void __init plat_mem_setup(void) dtb = phys_to_virt(fw_arg2); else if (fw_passed_dtb) /* UHI interface or appended dtb */ dtb = (void *)fw_passed_dtb; - else if (__dtb_start != __dtb_end) + else if (&__dtb_start != &__dtb_end) dtb = (void *)__dtb_start; else panic("no dtb found"); --- a/arch/mips/lantiq/prom.c +++ b/arch/mips/lantiq/prom.c @@ -79,7 +79,7 @@ void __init plat_mem_setup(void)
if (fw_passed_dtb) /* UHI interface */ dtb = (void *)fw_passed_dtb; - else if (__dtb_start != __dtb_end) + else if (&__dtb_start != &__dtb_end) dtb = (void *)__dtb_start; else panic("no dtb found"); --- a/arch/mips/pic32/pic32mzda/init.c +++ b/arch/mips/pic32/pic32mzda/init.c @@ -28,7 +28,7 @@ static ulong get_fdtaddr(void) if (fw_passed_dtb && !fw_arg2 && !fw_arg3) return (ulong)fw_passed_dtb;
- if (__dtb_start < __dtb_end) + if (&__dtb_start < &__dtb_end) ftaddr = (ulong)__dtb_start;
return ftaddr; --- a/arch/mips/ralink/of.c +++ b/arch/mips/ralink/of.c @@ -77,7 +77,7 @@ void __init plat_mem_setup(void) */ if (fw_passed_dtb) dtb = (void *)fw_passed_dtb; - else if (__dtb_start != __dtb_end) + else if (&__dtb_start != &__dtb_end) dtb = (void *)__dtb_start;
__dt_setup_arch(dtb);