Re: [Xen-devel] [PATCH 7/7] tools/kdd: mute spurious gcc warning
Hi,
At 16:32 +0200 on 06 Apr (1523032362), Marek Marczykowski-Górecki wrote:
> On Fri, Apr 06, 2018 at 09:56:05AM -0400, Boris Ostrovsky wrote:
> > Can we instead pre-compute the pointer to pacify the compiler? I haven't
> > seen the original error so I can't test it, but something like
>
> Nope, it doesn't help. But adding "if (offset > 0)" before that "+=
> offset" does...
> For me it looks like a gcc bug. Not sure how to deal with this. Enclose
> #pragma with #if __GNUC__ >= 8 ?
If the logic can be reshuffled so that gcc8 is happy with, that would
be better than silencing the warning, IMO. As far as I can see the
pointer is indeed safe[1], and if the compiler's going to decide
that it's not, I'd rather have the warning than have it silently
optimized out.
Cheers,
Tim.
[1] except a possible memcpy(dst, one-past-the-end-of-the-struct, 0),
which is not what's being complained of here, and is a good deal
too theological for me while I'm on my holiday.
> > diff --git a/tools/debugger/kdd/kdd.c b/tools/debugger/kdd/kdd.c
> > index 61d769e..1b048ac 100644
> > --- a/tools/debugger/kdd/kdd.c
> > +++ b/tools/debugger/kdd/kdd.c
> > @@ -688,6 +688,7 @@ static void kdd_handle_read_ctrl(kdd_state *s)
> > } else {
> > /* 32-bit control-register space starts at 0x[2]cc, for 84 bytes */
> > uint64_t offset = addr;
> > + void *ptr =
> > if (offset > 0x200)
> > offset -= 0x200;
> > offset -= 0xcc;
> > @@ -695,10 +696,8 @@ static void kdd_handle_read_ctrl(kdd_state *s)
> > KDD_LOG(s, "Request outside of known control space\n");
> > len = 0;
> > } else {
> > -#pragma GCC diagnostic push
> > -#pragma GCC diagnostic ignored "-Warray-bounds"
> > - memcpy(buf, ((uint8_t *)) + offset, len);
> > -#pragma GCC diagnostic pop
> > + ptr += offset;
> > + memcpy(buf, ptr, len);
> > }
> > }
> >
> > -boris
>
> --
> Best Regards,
> Marek Marczykowski-Górecki
> Invisible Things Lab
> A: Because it messes up the order in which people normally read text.
> Q: Why is top-posting such a bad thing?
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Re: [Xen-devel] [PATCH 7/7] tools/kdd: mute spurious gcc warning
On Fri, Apr 06, 2018 at 04:32:42PM +0200, Marek Marczykowski-Górecki wrote: > > >> cc1: warnings being treated as errors > > >> kdd.c:639: error: expected [error|warning|ignored] after ‘#pragma GCC > > >> diagnostic’ > > >> kdd.c:714: error: expected [error|warning|ignored] after ‘#pragma GCC > > >> diagnostic’ > > >> > > >> (Interestingly, my 64-bit build completed without issues) > > > Hmm... this is messy. > > > > > > If you have information about which version does what we can try to > > > enclose the #pragma's with #if __GCC__. > > > > > > Can we instead pre-compute the pointer to pacify the compiler? I haven't > > seen the original error so I can't test it, but something like > > Nope, it doesn't help. But adding "if (offset > 0)" before that "+= > offset" does... > For me it looks like a gcc bug. Not sure how to deal with this. Enclose > #pragma with #if __GNUC__ >= 8 ? I would be fine with this. Wei. ___ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
Re: [Xen-devel] [PATCH 7/7] tools/kdd: mute spurious gcc warning
On Fri, Apr 06, 2018 at 09:56:05AM -0400, Boris Ostrovsky wrote:
> On 04/06/2018 09:41 AM, Wei Liu wrote:
> > On Fri, Apr 06, 2018 at 09:39:50AM -0400, Boris Ostrovsky wrote:
> >> On 04/06/2018 09:07 AM, Wei Liu wrote:
> >>> On Fri, Apr 06, 2018 at 08:39:53AM -0400, Boris Ostrovsky wrote:
> On 04/04/2018 09:50 PM, Marek Marczykowski-Górecki wrote:
> > gcc-8 complains:
> >
> > kdd.c:698:13: error: 'memcpy' offset [-204, -717] is out of the
> > bounds [0, 216] of object 'ctrl' with type 'kdd_ctrl' {aka 'union
> > '} [-Werror=array-bounds]
> > memcpy(buf, ((uint8_t *)) + offset, len);
> > ^
> > kdd.c: In function 'kdd_select_callback':
> > kdd.c:642:14: note: 'ctrl' declared here
> > kdd_ctrl ctrl;
> > ^~~~
> >
> > But this is impossible - 'offset' is unsigned and correctly validated
> > few lines before.
> >
> > Signed-off-by: Marek Marczykowski-Górecki
> >
> > ---
> > tools/debugger/kdd/kdd.c | 3 +++
> > 1 file changed, 3 insertions(+)
> >
> > diff --git a/tools/debugger/kdd/kdd.c b/tools/debugger/kdd/kdd.c
> > index 1bd5dd5..61d769e 100644
> > --- a/tools/debugger/kdd/kdd.c
> > +++ b/tools/debugger/kdd/kdd.c
> > @@ -695,7 +695,10 @@ static void kdd_handle_read_ctrl(kdd_state *s)
> > KDD_LOG(s, "Request outside of known control space\n");
> > len = 0;
> > } else {
> > +#pragma GCC diagnostic push
> > +#pragma GCC diagnostic ignored "-Warray-bounds"
> > memcpy(buf, ((uint8_t *)) + offset, len);
> > +#pragma GCC diagnostic pop
> > }
> > }
> >
> Breaks 32-bit build, at least with my (ancient, gcc version 4.4.5
> 20101112 (Red Hat 4.4.5-2) (GCC)) compiler:
>
>
>
> kdd.c: In function ‘kdd_handle_read_ctrl’:
> kdd.c:698: error: #pragma GCC diagnostic not allowed inside functions
> kdd.c:699: error: #pragma GCC diagnostic not allowed inside functions
> kdd.c:701: error: #pragma GCC diagnostic not allowed inside functions
> make[5]: *** [kdd.o] Error 1
>
> >>> Does moving the relevant #pragma's outside of the function fix it?
> >> The additional problem with these pragmas is that apparently push/pop
> >> have been introduced in gcc 4.6.0:
> >>
> >> https://gcc.gnu.org/onlinedocs/gcc-4.6.0/gcc/Diagnostic-Pragmas.html#Diagnostic-Pragmas
> >>
> >> If you change release number to a lower one (e.g. 4.5.4) you won't see
> >> them.
> >>
> >> So I can move "diagnostic ignored" from inside the function and that
> >> will clear the "GCC diagnostic not allowed inside functions" error. But
> >> then push/pop are not recognized:
> >>
> >> cc1: warnings being treated as errors
> >> kdd.c:639: error: expected [error|warning|ignored] after ‘#pragma GCC
> >> diagnostic’
> >> kdd.c:714: error: expected [error|warning|ignored] after ‘#pragma GCC
> >> diagnostic’
> >>
> >> (Interestingly, my 64-bit build completed without issues)
> > Hmm... this is messy.
> >
> > If you have information about which version does what we can try to
> > enclose the #pragma's with #if __GCC__.
>
>
> Can we instead pre-compute the pointer to pacify the compiler? I haven't
> seen the original error so I can't test it, but something like
Nope, it doesn't help. But adding "if (offset > 0)" before that "+=
offset" does...
For me it looks like a gcc bug. Not sure how to deal with this. Enclose
#pragma with #if __GNUC__ >= 8 ?
> diff --git a/tools/debugger/kdd/kdd.c b/tools/debugger/kdd/kdd.c
> index 61d769e..1b048ac 100644
> --- a/tools/debugger/kdd/kdd.c
> +++ b/tools/debugger/kdd/kdd.c
> @@ -688,6 +688,7 @@ static void kdd_handle_read_ctrl(kdd_state *s)
> } else {
> /* 32-bit control-register space starts at 0x[2]cc, for 84 bytes */
> uint64_t offset = addr;
> + void *ptr =
> if (offset > 0x200)
> offset -= 0x200;
> offset -= 0xcc;
> @@ -695,10 +696,8 @@ static void kdd_handle_read_ctrl(kdd_state *s)
> KDD_LOG(s, "Request outside of known control space\n");
> len = 0;
> } else {
> -#pragma GCC diagnostic push
> -#pragma GCC diagnostic ignored "-Warray-bounds"
> - memcpy(buf, ((uint8_t *)) + offset, len);
> -#pragma GCC diagnostic pop
> + ptr += offset;
> + memcpy(buf, ptr, len);
> }
> }
>
> -boris
--
Best Regards,
Marek Marczykowski-Górecki
Invisible Things Lab
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
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Re: [Xen-devel] [PATCH 7/7] tools/kdd: mute spurious gcc warning
On 04/06/2018 09:41 AM, Wei Liu wrote:
> On Fri, Apr 06, 2018 at 09:39:50AM -0400, Boris Ostrovsky wrote:
>> On 04/06/2018 09:07 AM, Wei Liu wrote:
>>> On Fri, Apr 06, 2018 at 08:39:53AM -0400, Boris Ostrovsky wrote:
On 04/04/2018 09:50 PM, Marek Marczykowski-Górecki wrote:
> gcc-8 complains:
>
> kdd.c:698:13: error: 'memcpy' offset [-204, -717] is out of the
> bounds [0, 216] of object 'ctrl' with type 'kdd_ctrl' {aka 'union
> '} [-Werror=array-bounds]
> memcpy(buf, ((uint8_t *)) + offset, len);
> ^
> kdd.c: In function 'kdd_select_callback':
> kdd.c:642:14: note: 'ctrl' declared here
> kdd_ctrl ctrl;
> ^~~~
>
> But this is impossible - 'offset' is unsigned and correctly validated
> few lines before.
>
> Signed-off-by: Marek Marczykowski-Górecki
>
> ---
> tools/debugger/kdd/kdd.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/tools/debugger/kdd/kdd.c b/tools/debugger/kdd/kdd.c
> index 1bd5dd5..61d769e 100644
> --- a/tools/debugger/kdd/kdd.c
> +++ b/tools/debugger/kdd/kdd.c
> @@ -695,7 +695,10 @@ static void kdd_handle_read_ctrl(kdd_state *s)
> KDD_LOG(s, "Request outside of known control space\n");
> len = 0;
> } else {
> +#pragma GCC diagnostic push
> +#pragma GCC diagnostic ignored "-Warray-bounds"
> memcpy(buf, ((uint8_t *)) + offset, len);
> +#pragma GCC diagnostic pop
> }
> }
>
Breaks 32-bit build, at least with my (ancient, gcc version 4.4.5
20101112 (Red Hat 4.4.5-2) (GCC)) compiler:
kdd.c: In function ‘kdd_handle_read_ctrl’:
kdd.c:698: error: #pragma GCC diagnostic not allowed inside functions
kdd.c:699: error: #pragma GCC diagnostic not allowed inside functions
kdd.c:701: error: #pragma GCC diagnostic not allowed inside functions
make[5]: *** [kdd.o] Error 1
>>> Does moving the relevant #pragma's outside of the function fix it?
>> The additional problem with these pragmas is that apparently push/pop
>> have been introduced in gcc 4.6.0:
>>
>> https://gcc.gnu.org/onlinedocs/gcc-4.6.0/gcc/Diagnostic-Pragmas.html#Diagnostic-Pragmas
>>
>> If you change release number to a lower one (e.g. 4.5.4) you won't see them.
>>
>> So I can move "diagnostic ignored" from inside the function and that
>> will clear the "GCC diagnostic not allowed inside functions" error. But
>> then push/pop are not recognized:
>>
>> cc1: warnings being treated as errors
>> kdd.c:639: error: expected [error|warning|ignored] after ‘#pragma GCC
>> diagnostic’
>> kdd.c:714: error: expected [error|warning|ignored] after ‘#pragma GCC
>> diagnostic’
>>
>> (Interestingly, my 64-bit build completed without issues)
> Hmm... this is messy.
>
> If you have information about which version does what we can try to
> enclose the #pragma's with #if __GCC__.
Can we instead pre-compute the pointer to pacify the compiler? I haven't
seen the original error so I can't test it, but something like
diff --git a/tools/debugger/kdd/kdd.c b/tools/debugger/kdd/kdd.c
index 61d769e..1b048ac 100644
--- a/tools/debugger/kdd/kdd.c
+++ b/tools/debugger/kdd/kdd.c
@@ -688,6 +688,7 @@ static void kdd_handle_read_ctrl(kdd_state *s)
} else {
/* 32-bit control-register space starts at 0x[2]cc, for 84 bytes */
uint64_t offset = addr;
+ void *ptr =
if (offset > 0x200)
offset -= 0x200;
offset -= 0xcc;
@@ -695,10 +696,8 @@ static void kdd_handle_read_ctrl(kdd_state *s)
KDD_LOG(s, "Request outside of known control space\n");
len = 0;
} else {
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Warray-bounds"
- memcpy(buf, ((uint8_t *)) + offset, len);
-#pragma GCC diagnostic pop
+ ptr += offset;
+ memcpy(buf, ptr, len);
}
}
-boris
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Re: [Xen-devel] [PATCH 7/7] tools/kdd: mute spurious gcc warning
On Fri, Apr 06, 2018 at 09:39:50AM -0400, Boris Ostrovsky wrote:
> On 04/06/2018 09:07 AM, Wei Liu wrote:
> > On Fri, Apr 06, 2018 at 08:39:53AM -0400, Boris Ostrovsky wrote:
> >> On 04/04/2018 09:50 PM, Marek Marczykowski-Górecki wrote:
> >>> gcc-8 complains:
> >>>
> >>> kdd.c:698:13: error: 'memcpy' offset [-204, -717] is out of the
> >>> bounds [0, 216] of object 'ctrl' with type 'kdd_ctrl' {aka 'union
> >>> '} [-Werror=array-bounds]
> >>> memcpy(buf, ((uint8_t *)) + offset, len);
> >>> ^
> >>> kdd.c: In function 'kdd_select_callback':
> >>> kdd.c:642:14: note: 'ctrl' declared here
> >>> kdd_ctrl ctrl;
> >>> ^~~~
> >>>
> >>> But this is impossible - 'offset' is unsigned and correctly validated
> >>> few lines before.
> >>>
> >>> Signed-off-by: Marek Marczykowski-Górecki
> >>>
> >>> ---
> >>> tools/debugger/kdd/kdd.c | 3 +++
> >>> 1 file changed, 3 insertions(+)
> >>>
> >>> diff --git a/tools/debugger/kdd/kdd.c b/tools/debugger/kdd/kdd.c
> >>> index 1bd5dd5..61d769e 100644
> >>> --- a/tools/debugger/kdd/kdd.c
> >>> +++ b/tools/debugger/kdd/kdd.c
> >>> @@ -695,7 +695,10 @@ static void kdd_handle_read_ctrl(kdd_state *s)
> >>> KDD_LOG(s, "Request outside of known control space\n");
> >>> len = 0;
> >>> } else {
> >>> +#pragma GCC diagnostic push
> >>> +#pragma GCC diagnostic ignored "-Warray-bounds"
> >>> memcpy(buf, ((uint8_t *)) + offset, len);
> >>> +#pragma GCC diagnostic pop
> >>> }
> >>> }
> >>>
> >>
> >> Breaks 32-bit build, at least with my (ancient, gcc version 4.4.5
> >> 20101112 (Red Hat 4.4.5-2) (GCC)) compiler:
> >>
> >>
> >>
> >> kdd.c: In function ‘kdd_handle_read_ctrl’:
> >> kdd.c:698: error: #pragma GCC diagnostic not allowed inside functions
> >> kdd.c:699: error: #pragma GCC diagnostic not allowed inside functions
> >> kdd.c:701: error: #pragma GCC diagnostic not allowed inside functions
> >> make[5]: *** [kdd.o] Error 1
> >>
> > Does moving the relevant #pragma's outside of the function fix it?
>
> The additional problem with these pragmas is that apparently push/pop
> have been introduced in gcc 4.6.0:
>
> https://gcc.gnu.org/onlinedocs/gcc-4.6.0/gcc/Diagnostic-Pragmas.html#Diagnostic-Pragmas
>
> If you change release number to a lower one (e.g. 4.5.4) you won't see them.
>
> So I can move "diagnostic ignored" from inside the function and that
> will clear the "GCC diagnostic not allowed inside functions" error. But
> then push/pop are not recognized:
>
> cc1: warnings being treated as errors
> kdd.c:639: error: expected [error|warning|ignored] after ‘#pragma GCC
> diagnostic’
> kdd.c:714: error: expected [error|warning|ignored] after ‘#pragma GCC
> diagnostic’
>
> (Interestingly, my 64-bit build completed without issues)
Hmm... this is messy.
If you have information about which version does what we can try to
enclose the #pragma's with #if __GCC__.
Wei.
>
> -boris
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Re: [Xen-devel] [PATCH 7/7] tools/kdd: mute spurious gcc warning
On 04/06/2018 09:07 AM, Wei Liu wrote:
> On Fri, Apr 06, 2018 at 08:39:53AM -0400, Boris Ostrovsky wrote:
>> On 04/04/2018 09:50 PM, Marek Marczykowski-Górecki wrote:
>>> gcc-8 complains:
>>>
>>> kdd.c:698:13: error: 'memcpy' offset [-204, -717] is out of the bounds
>>> [0, 216] of object 'ctrl' with type 'kdd_ctrl' {aka 'union '}
>>> [-Werror=array-bounds]
>>> memcpy(buf, ((uint8_t *)) + offset, len);
>>> ^
>>> kdd.c: In function 'kdd_select_callback':
>>> kdd.c:642:14: note: 'ctrl' declared here
>>> kdd_ctrl ctrl;
>>> ^~~~
>>>
>>> But this is impossible - 'offset' is unsigned and correctly validated
>>> few lines before.
>>>
>>> Signed-off-by: Marek Marczykowski-Górecki
>>> ---
>>> tools/debugger/kdd/kdd.c | 3 +++
>>> 1 file changed, 3 insertions(+)
>>>
>>> diff --git a/tools/debugger/kdd/kdd.c b/tools/debugger/kdd/kdd.c
>>> index 1bd5dd5..61d769e 100644
>>> --- a/tools/debugger/kdd/kdd.c
>>> +++ b/tools/debugger/kdd/kdd.c
>>> @@ -695,7 +695,10 @@ static void kdd_handle_read_ctrl(kdd_state *s)
>>> KDD_LOG(s, "Request outside of known control space\n");
>>> len = 0;
>>> } else {
>>> +#pragma GCC diagnostic push
>>> +#pragma GCC diagnostic ignored "-Warray-bounds"
>>> memcpy(buf, ((uint8_t *)) + offset, len);
>>> +#pragma GCC diagnostic pop
>>> }
>>> }
>>>
>>
>> Breaks 32-bit build, at least with my (ancient, gcc version 4.4.5
>> 20101112 (Red Hat 4.4.5-2) (GCC)) compiler:
>>
>>
>>
>> kdd.c: In function ‘kdd_handle_read_ctrl’:
>> kdd.c:698: error: #pragma GCC diagnostic not allowed inside functions
>> kdd.c:699: error: #pragma GCC diagnostic not allowed inside functions
>> kdd.c:701: error: #pragma GCC diagnostic not allowed inside functions
>> make[5]: *** [kdd.o] Error 1
>>
> Does moving the relevant #pragma's outside of the function fix it?
The additional problem with these pragmas is that apparently push/pop
have been introduced in gcc 4.6.0:
https://gcc.gnu.org/onlinedocs/gcc-4.6.0/gcc/Diagnostic-Pragmas.html#Diagnostic-Pragmas
If you change release number to a lower one (e.g. 4.5.4) you won't see them.
So I can move "diagnostic ignored" from inside the function and that
will clear the "GCC diagnostic not allowed inside functions" error. But
then push/pop are not recognized:
cc1: warnings being treated as errors
kdd.c:639: error: expected [error|warning|ignored] after ‘#pragma GCC
diagnostic’
kdd.c:714: error: expected [error|warning|ignored] after ‘#pragma GCC
diagnostic’
(Interestingly, my 64-bit build completed without issues)
-boris
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Re: [Xen-devel] [PATCH 7/7] tools/kdd: mute spurious gcc warning
On Fri, Apr 06, 2018 at 08:39:53AM -0400, Boris Ostrovsky wrote:
> On 04/04/2018 09:50 PM, Marek Marczykowski-Górecki wrote:
> > gcc-8 complains:
> >
> > kdd.c:698:13: error: 'memcpy' offset [-204, -717] is out of the bounds
> > [0, 216] of object 'ctrl' with type 'kdd_ctrl' {aka 'union '}
> > [-Werror=array-bounds]
> > memcpy(buf, ((uint8_t *)) + offset, len);
> > ^
> > kdd.c: In function 'kdd_select_callback':
> > kdd.c:642:14: note: 'ctrl' declared here
> > kdd_ctrl ctrl;
> > ^~~~
> >
> > But this is impossible - 'offset' is unsigned and correctly validated
> > few lines before.
> >
> > Signed-off-by: Marek Marczykowski-Górecki
> > ---
> > tools/debugger/kdd/kdd.c | 3 +++
> > 1 file changed, 3 insertions(+)
> >
> > diff --git a/tools/debugger/kdd/kdd.c b/tools/debugger/kdd/kdd.c
> > index 1bd5dd5..61d769e 100644
> > --- a/tools/debugger/kdd/kdd.c
> > +++ b/tools/debugger/kdd/kdd.c
> > @@ -695,7 +695,10 @@ static void kdd_handle_read_ctrl(kdd_state *s)
> > KDD_LOG(s, "Request outside of known control space\n");
> > len = 0;
> > } else {
> > +#pragma GCC diagnostic push
> > +#pragma GCC diagnostic ignored "-Warray-bounds"
> > memcpy(buf, ((uint8_t *)) + offset, len);
> > +#pragma GCC diagnostic pop
> > }
> > }
> >
>
>
> Breaks 32-bit build, at least with my (ancient, gcc version 4.4.5
> 20101112 (Red Hat 4.4.5-2) (GCC)) compiler:
>
>
>
> kdd.c: In function ‘kdd_handle_read_ctrl’:
> kdd.c:698: error: #pragma GCC diagnostic not allowed inside functions
> kdd.c:699: error: #pragma GCC diagnostic not allowed inside functions
> kdd.c:701: error: #pragma GCC diagnostic not allowed inside functions
> make[5]: *** [kdd.o] Error 1
>
Does moving the relevant #pragma's outside of the function fix it?
Wei.
>
> -boris
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Re: [Xen-devel] [PATCH 7/7] tools/kdd: mute spurious gcc warning
On 04/04/2018 09:50 PM, Marek Marczykowski-Górecki wrote:
> gcc-8 complains:
>
> kdd.c:698:13: error: 'memcpy' offset [-204, -717] is out of the bounds
> [0, 216] of object 'ctrl' with type 'kdd_ctrl' {aka 'union '}
> [-Werror=array-bounds]
> memcpy(buf, ((uint8_t *)) + offset, len);
> ^
> kdd.c: In function 'kdd_select_callback':
> kdd.c:642:14: note: 'ctrl' declared here
> kdd_ctrl ctrl;
> ^~~~
>
> But this is impossible - 'offset' is unsigned and correctly validated
> few lines before.
>
> Signed-off-by: Marek Marczykowski-Górecki
> ---
> tools/debugger/kdd/kdd.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/tools/debugger/kdd/kdd.c b/tools/debugger/kdd/kdd.c
> index 1bd5dd5..61d769e 100644
> --- a/tools/debugger/kdd/kdd.c
> +++ b/tools/debugger/kdd/kdd.c
> @@ -695,7 +695,10 @@ static void kdd_handle_read_ctrl(kdd_state *s)
> KDD_LOG(s, "Request outside of known control space\n");
> len = 0;
> } else {
> +#pragma GCC diagnostic push
> +#pragma GCC diagnostic ignored "-Warray-bounds"
> memcpy(buf, ((uint8_t *)) + offset, len);
> +#pragma GCC diagnostic pop
> }
> }
>
Breaks 32-bit build, at least with my (ancient, gcc version 4.4.5
20101112 (Red Hat 4.4.5-2) (GCC)) compiler:
kdd.c: In function ‘kdd_handle_read_ctrl’:
kdd.c:698: error: #pragma GCC diagnostic not allowed inside functions
kdd.c:699: error: #pragma GCC diagnostic not allowed inside functions
kdd.c:701: error: #pragma GCC diagnostic not allowed inside functions
make[5]: *** [kdd.o] Error 1
-boris
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[Xen-devel] [PATCH 7/7] tools/kdd: mute spurious gcc warning
gcc-8 complains:
kdd.c:698:13: error: 'memcpy' offset [-204, -717] is out of the bounds [0,
216] of object 'ctrl' with type 'kdd_ctrl' {aka 'union '}
[-Werror=array-bounds]
memcpy(buf, ((uint8_t *)) + offset, len);
^
kdd.c: In function 'kdd_select_callback':
kdd.c:642:14: note: 'ctrl' declared here
kdd_ctrl ctrl;
^~~~
But this is impossible - 'offset' is unsigned and correctly validated
few lines before.
Signed-off-by: Marek Marczykowski-Górecki
---
tools/debugger/kdd/kdd.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/tools/debugger/kdd/kdd.c b/tools/debugger/kdd/kdd.c
index 1bd5dd5..61d769e 100644
--- a/tools/debugger/kdd/kdd.c
+++ b/tools/debugger/kdd/kdd.c
@@ -695,7 +695,10 @@ static void kdd_handle_read_ctrl(kdd_state *s)
KDD_LOG(s, "Request outside of known control space\n");
len = 0;
} else {
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Warray-bounds"
memcpy(buf, ((uint8_t *)) + offset, len);
+#pragma GCC diagnostic pop
}
}
--
git-series 0.9.1
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