| Message ID | 20210105201827.51766-1-natechancellor@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | d422c6c0644bccbb1ebeefffa51f35cec3019517 |
| Headers | show |
| Series | MIPS: Use address-of operator on section symbols | expand |
On 1/5/21 12:18 PM, Nathan Chancellor wrote: > 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>
On Tue, Jan 05, 2021 at 01:18:27PM -0700, Nathan Chancellor wrote: > 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> > --- > 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(-) applied to mips-next. Thomas.
diff --git a/arch/mips/bmips/setup.c b/arch/mips/bmips/setup.c index 19308df5f577..1b06b25aea87 100644 --- 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"); diff --git a/arch/mips/lantiq/prom.c b/arch/mips/lantiq/prom.c index 51a218f04fe0..3f568f5aae2d 100644 --- 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"); diff --git a/arch/mips/pic32/pic32mzda/init.c b/arch/mips/pic32/pic32mzda/init.c index 50f376f058f4..f232c77ff526 100644 --- 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; diff --git a/arch/mips/ralink/of.c b/arch/mips/ralink/of.c index cbae9d23ab7f..2c9af61efc20 100644 --- a/arch/mips/ralink/of.c +++ b/arch/mips/ralink/of.c @@ -75,7 +75,7 @@ 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);
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> --- 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(-) base-commit: 36bbbd0e234d817938bdc52121a0f5473b3e58f5