ia64: Fix build error due to switch case label appearing next to declaration

[PATCH] ia64: Fix build error due to switch case label appearing next to declaration

Posted by James Morse 2 years, 8 months ago

Since commit aa06a9bd8533 ("ia64: fix clock_getres(CLOCK_MONOTONIC) to
report ITC frequency"), gcc 10.1.0 fails to build ia64 with the gnomic:
| ../arch/ia64/kernel/sys_ia64.c: In function 'ia64_clock_getres':
| ../arch/ia64/kernel/sys_ia64.c:189:3: error: a label can only be part of a statement and a declaration is not a statement
|   189 |   s64 tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, local_cpu_data->itc_freq);

This line appears immediately after a case label in a switch.

Move the declarations out of the case, to the top of the function.

Fixes: aa06a9bd8533 ("ia64: fix clock_getres(CLOCK_MONOTONIC) to report ITC frequency")
Signed-off-by: James Morse <james.morse@arm.com>
---
Found when build testing another series.
I've only build tested this.

 arch/ia64/kernel/sys_ia64.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/ia64/kernel/sys_ia64.c b/arch/ia64/kernel/sys_ia64.c
index f6a502e8f02c..6e948d015332 100644
--- a/arch/ia64/kernel/sys_ia64.c
+++ b/arch/ia64/kernel/sys_ia64.c
@@ -170,6 +170,9 @@ ia64_mremap (unsigned long addr, unsigned long old_len, unsigned long new_len, u
 asmlinkage long
 ia64_clock_getres(const clockid_t which_clock, struct __kernel_timespec __user *tp)
 {
+	struct timespec64 rtn_tp;
+	s64 tick_ns;
+
 	/*
 	 * ia64's clock_gettime() syscall is implemented as a vdso call
 	 * fsys_clock_gettime(). Currently it handles only
@@ -185,8 +188,8 @@ ia64_clock_getres(const clockid_t which_clock, struct __kernel_timespec __user *
 	switch (which_clock) {
 	case CLOCK_REALTIME:
 	case CLOCK_MONOTONIC:
-		s64 tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, local_cpu_data->itc_freq);
-		struct timespec64 rtn_tp = ns_to_timespec64(tick_ns);
+		tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, local_cpu_data->itc_freq);
+		rtn_tp = ns_to_timespec64(tick_ns);
 		return put_timespec64(&rtn_tp, tp);
 	}
 
-- 
2.30.2

Re: [PATCH] ia64: Fix build error due to switch case label appearing next to declaration

Posted by Andrew Morton 2 years, 7 months ago

On Tue, 17 Jan 2023 15:16:32 +0000 James Morse <james.morse@arm.com> wrote:

> Since commit aa06a9bd8533 ("ia64: fix clock_getres(CLOCK_MONOTONIC) to
> report ITC frequency"), gcc 10.1.0 fails to build ia64 with the gnomic:
> | ../arch/ia64/kernel/sys_ia64.c: In function 'ia64_clock_getres':
> | ../arch/ia64/kernel/sys_ia64.c:189:3: error: a label can only be part of a statement and a declaration is not a statement
> |   189 |   s64 tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, local_cpu_data->itc_freq);
> 
> ...
>
> @@ -185,8 +188,8 @@ ia64_clock_getres(const clockid_t which_clock, struct __kernel_timespec __user *
>  	switch (which_clock) {
>  	case CLOCK_REALTIME:
>  	case CLOCK_MONOTONIC:
> -		s64 tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, local_cpu_data->itc_freq);
> -		struct timespec64 rtn_tp = ns_to_timespec64(tick_ns);
> +		tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, local_cpu_data->itc_freq);
> +		rtn_tp = ns_to_timespec64(tick_ns);
>  		return put_timespec64(&rtn_tp, tp);
>  	}
>  

Huh, how did that sneak through.  We usually use an extra set of braces
for this.

Thanks, I'll add cc:stable to this.

Re: [PATCH] ia64: Fix build error due to switch case label appearing next to declaration

Posted by Sergei Trofimovich 2 years, 8 months ago

On Tue, 17 Jan 2023 15:16:32 +0000
James Morse <james.morse@arm.com> wrote:

> Since commit aa06a9bd8533 ("ia64: fix clock_getres(CLOCK_MONOTONIC) to
> report ITC frequency"), gcc 10.1.0 fails to build ia64 with the gnomic:
> | ../arch/ia64/kernel/sys_ia64.c: In function 'ia64_clock_getres':
> | ../arch/ia64/kernel/sys_ia64.c:189:3: error: a label can only be part of a statement and a declaration is not a statement
> |   189 |   s64 tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, local_cpu_data->itc_freq);
> 
> This line appears immediately after a case label in a switch.
> 
> Move the declarations out of the case, to the top of the function.
> 
> Fixes: aa06a9bd8533 ("ia64: fix clock_getres(CLOCK_MONOTONIC) to report ITC frequency")
> Signed-off-by: James Morse <james.morse@arm.com>

Out of curiosity what compiler version behaves like that? I think I and
matoro build-/run-tested it on gcc-12 and maybe gcc-11.

Thank you!

Reviewed-by: Sergei Trofimovich <slyich@gmail.com>

> ---
> Found when build testing another series.
> I've only build tested this.
> 
>  arch/ia64/kernel/sys_ia64.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/ia64/kernel/sys_ia64.c b/arch/ia64/kernel/sys_ia64.c
> index f6a502e8f02c..6e948d015332 100644
> --- a/arch/ia64/kernel/sys_ia64.c
> +++ b/arch/ia64/kernel/sys_ia64.c
> @@ -170,6 +170,9 @@ ia64_mremap (unsigned long addr, unsigned long old_len, unsigned long new_len, u
>  asmlinkage long
>  ia64_clock_getres(const clockid_t which_clock, struct __kernel_timespec __user *tp)
>  {
> +	struct timespec64 rtn_tp;
> +	s64 tick_ns;
> +
>  	/*
>  	 * ia64's clock_gettime() syscall is implemented as a vdso call
>  	 * fsys_clock_gettime(). Currently it handles only
> @@ -185,8 +188,8 @@ ia64_clock_getres(const clockid_t which_clock, struct __kernel_timespec __user *
>  	switch (which_clock) {
>  	case CLOCK_REALTIME:
>  	case CLOCK_MONOTONIC:
> -		s64 tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, local_cpu_data->itc_freq);
> -		struct timespec64 rtn_tp = ns_to_timespec64(tick_ns);
> +		tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, local_cpu_data->itc_freq);
> +		rtn_tp = ns_to_timespec64(tick_ns);
>  		return put_timespec64(&rtn_tp, tp);
>  	}
>  
> -- 
> 2.30.2
> 


-- 

  Sergei

Re: [PATCH] ia64: Fix build error due to switch case label appearing next to declaration

Posted by James Morse 2 years, 7 months ago

Hi Sergei,

On 17/01/2023 19:31, Sergei Trofimovich wrote:
> On Tue, 17 Jan 2023 15:16:32 +0000
> James Morse <james.morse@arm.com> wrote:
> 
>> Since commit aa06a9bd8533 ("ia64: fix clock_getres(CLOCK_MONOTONIC) to
>> report ITC frequency"), gcc 10.1.0 fails to build ia64 with the gnomic:
>> | ../arch/ia64/kernel/sys_ia64.c: In function 'ia64_clock_getres':
>> | ../arch/ia64/kernel/sys_ia64.c:189:3: error: a label can only be part of a statement and a declaration is not a statement
>> |   189 |   s64 tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, local_cpu_data->itc_freq);
>>
>> This line appears immediately after a case label in a switch.
>>
>> Move the declarations out of the case, to the top of the function.
>>
>> Fixes: aa06a9bd8533 ("ia64: fix clock_getres(CLOCK_MONOTONIC) to report ITC frequency")
>> Signed-off-by: James Morse <james.morse@arm.com>

> Out of curiosity what compiler version behaves like that? I think I and
> matoro build-/run-tested it on gcc-12 and maybe gcc-11.

| # ia64-linux-gcc --version
| ia64-linux-gcc (GCC) 10.1.0
| Copyright (C) 2020 Free Software Foundation, Inc.
| This is free software; see the source for copying conditions.  There is NO
| warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

The toolchain originally came from https://mirrors.edge.kernel.org/pub/tools/crosstool/

The really odd thing I'm doing is cross compiling for ia64 on arm64 ... but I wouldn't
have thought the toolchain configuration was any different.


> Thank you!
> 
> Reviewed-by: Sergei Trofimovich <slyich@gmail.com>


Thanks,

James

Re: [PATCH] ia64: Fix build error due to switch case label appearing next to declaration

Posted by John Paul Adrian Glaubitz 2 years, 8 months ago

Hi James!

On 1/17/23 16:16, James Morse wrote:
> Since commit aa06a9bd8533 ("ia64: fix clock_getres(CLOCK_MONOTONIC) to
> report ITC frequency"), gcc 10.1.0 fails to build ia64 with the gnomic:
> | ../arch/ia64/kernel/sys_ia64.c: In function 'ia64_clock_getres':
> | ../arch/ia64/kernel/sys_ia64.c:189:3: error: a label can only be part of a statement and a declaration is not a statement
> |   189 |   s64 tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, local_cpu_data->itc_freq);
> 
> This line appears immediately after a case label in a switch.
> 
> Move the declarations out of the case, to the top of the function.
> 
> Fixes: aa06a9bd8533 ("ia64: fix clock_getres(CLOCK_MONOTONIC) to report ITC frequency")
> Signed-off-by: James Morse <james.morse@arm.com>
> ---
> Found when build testing another series.
> I've only build tested this.
> 
>   arch/ia64/kernel/sys_ia64.c | 7 +++++--
>   1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/ia64/kernel/sys_ia64.c b/arch/ia64/kernel/sys_ia64.c
> index f6a502e8f02c..6e948d015332 100644
> --- a/arch/ia64/kernel/sys_ia64.c
> +++ b/arch/ia64/kernel/sys_ia64.c
> @@ -170,6 +170,9 @@ ia64_mremap (unsigned long addr, unsigned long old_len, unsigned long new_len, u
>   asmlinkage long
>   ia64_clock_getres(const clockid_t which_clock, struct __kernel_timespec __user *tp)
>   {
> +	struct timespec64 rtn_tp;
> +	s64 tick_ns;
> +
>   	/*
>   	 * ia64's clock_gettime() syscall is implemented as a vdso call
>   	 * fsys_clock_gettime(). Currently it handles only
> @@ -185,8 +188,8 @@ ia64_clock_getres(const clockid_t which_clock, struct __kernel_timespec __user *
>   	switch (which_clock) {
>   	case CLOCK_REALTIME:
>   	case CLOCK_MONOTONIC:
> -		s64 tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, local_cpu_data->itc_freq);
> -		struct timespec64 rtn_tp = ns_to_timespec64(tick_ns);
> +		tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, local_cpu_data->itc_freq);
> +		rtn_tp = ns_to_timespec64(tick_ns);
>   		return put_timespec64(&rtn_tp, tp);
>   	}
>   

Thanks for the patch. I just gave it a try and it didn't make any difference for me.

The kernel builds fine in both cases (with CONFIG_WERROR disabled) on 6e50979a9c87.

I can boot-test the patch later tonight with my RX2600 at home.

Adrian

-- 
  .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer
`. `'   Physicist
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