[COMMITTED] gas: sframe: do not test whether offsetT exceeds INT64_MIN..INT64_MAX

[Jan Beulich]

On 13.01.2026 17:07, Jens Remus wrote:
> On 1/13/2026 4:52 PM, Jan Beulich wrote:
>> On 13.01.2026 16:46, Jens Remus wrote:
>>> On 1/13/2026 4:37 PM, Jan Beulich wrote:
>>>> On 13.01.2026 16:27, Jens Remus wrote:
>>>>> On 1/13/2026 2:59 PM, Jan Beulich wrote:
>>>>>> On 13.01.2026 14:24, Jens Remus wrote:
>>>>>>> A value of type offsetT, which is either a signed 32-bit or 64-bit
>>>>>>> integer, cannot exceed the range of INT64_MIN..INT64_MAX.  This
>>>>>>> resolves the following compile error:
>>>>>>>
>>>>>>> ../../binutils-gdb/gas/gen-sframe.c: In function ‘get_offset_size_in_bytes’:
>>>>>>> ../../binutils-gdb/gas/gen-sframe.c:213:45: error: comparison is always true due to limited range of data type [-Werror=type-limits]
>>>>>>>   213 |   else if ((sizeof (offsetT) > 4) && (value <= INT64_MAX && value >= INT64_MIN))
>>>>>>>       |                                             ^~
>>>>>>> ../../binutils-gdb/gas/gen-sframe.c:213:67: error: comparison is always true due to limited range of data type [-Werror=type-limits]
>>>>>>>   213 |   else if ((sizeof (offsetT) > 4) && (value <= INT64_MAX && value >= INT64_MIN))
>>>>>>
>>>>>> This same error ...
>>>>>>
>>>>>>> --- a/gas/gen-sframe.c
>>>>>>> +++ b/gas/gen-sframe.c
>>>>>>> @@ -210,7 +210,7 @@ get_offset_size_in_bytes (offsetT value)
>>>>>>>      size = 2;
>>>>>>>    else if (value <= INT32_MAX && value >= INT32_MIN)
>>>>>>
>>>>>> ... will trigger here on a !BFD64 build.
>>>>>
>>>>> Argh!  Good catch! Thanks for letting me know!  How do I resolve this
>>>>> properly?  Shall I commit another fix "gas: sframe: do not test whether
>>>>> 32-bit offsetT exceeds INT32_MIN..INT32_MAX" or shall I better revert
>>>>> both commits and start fresh with a v3 review of the initial patch?
>>>>
>>>> Incrementally is fine with me.
>>>>
>>>>> I propose the following as solution:
>>>>>
>>>>>   if (value <= INT8_MAX && value >= INT8_MIN)
>>>>>     size = 1;
>>>>>   else if (value <= INT16_MAX && value >= INT16_MIN)
>>>>>     size = 2;
>>>>>   else if ((sizeof (offsetT) == 4) || (value <= INT32_MAX && value >= INT32_MIN))
>>>>
>>>> Depending on the internal workings of compilers, this may still trigger
>>>> the same diagnostic. I.e. depending on whether the rhs of the || is
>>>> eliminated ahead of or after when these kinds of warnings are issued.
>>>> A pre-processor conditional involving BFD64 may be better.
>>>
>>> Is the following patch ok?
>>
>> In principle yes; the part I need to defer to Indu or you is whether ...
>>
>>> --- a/gas/gen-sframe.c
>>> +++ b/gas/gen-sframe.c
>>> @@ -208,10 +208,15 @@ get_offset_size_in_bytes (offsetT value)
>>>      size = 1;
>>>    else if (value <= INT16_MAX && value >= INT16_MIN)
>>>      size = 2;
>>> +#ifdef BFD64
>>>    else if (value <= INT32_MAX && value >= INT32_MIN)
>>>      size = 4;
>>> -  else if (sizeof (offsetT) > 4)
>>> +  else
>>>      size = 8;
>>> +#else
>>> +  else
>>> +    size = 4;
>>> +#endif
>>
>> ... 8-byte sizes really are entirely impossible to use when !BFD64. Since
>> it's an offsetT that is passed in, this would seem logical, but I'd rather
>> have Indu / you double-check.
> 
> Condensed excerpt from gas/as.h:
> 
> #ifdef BFD64
> typedef int64_t bfd_signed_vma;
> #else /* not BFD64  */
> typedef int32_t bfd_signed_vma;
> #endif /* not BFD64  */
> 
> typedef bfd_signed_vma offsetT;
> 
> If BFD64, then offsetT is a signed 64-bit integer.  Otherwise it is a
> signed 32-bit integer.  As a result it is impossible for !BFD64 to have
> a 64-bit offsetT.

Sure, hence my reference to offsetT in my earlier reply.

> Or were you concerned whether SFrame would be broken for !BFD64 targets
> in general?  AFAIK SFrame does only allow 8-bit, 16-bit, and 32-bit
> SFrame offsets.  64-bit ones are not supported:
> 
> Excerpt from gas/gen-sframe.c:
> 
> #define SFRAME_FRE_OFFSET_FUNC_MAP_INDEX_1B  0 /* SFRAME_FRE_OFFSET_1B.  */
> #define SFRAME_FRE_OFFSET_FUNC_MAP_INDEX_2B  1 /* SFRAME_FRE_OFFSET_2B.  */
> #define SFRAME_FRE_OFFSET_FUNC_MAP_INDEX_4B  2 /* SFRAME_FRE_OFFSET_4B.  */
> #define SFRAME_FRE_OFFSET_FUNC_MAP_INDEX_8B  3 /* Not supported in SFrame.  */

Then why is size 8 even a possible return value of the function?

Jan