[PATCH v11 23/25] gnu directives: gas/readelf tests for gnu attributes v2

[Jan Beulich]

On 15.01.2026 18:25, Matthieu Longo wrote:
> On 15/01/2026 15:24, Jan Beulich wrote:
>> On 15.01.2026 15:18, Matthieu Longo wrote:
>>> On 15/01/2026 08:39, Jan Beulich wrote:
>>>> On 14.01.2026 17:50, Matthieu Longo wrote:
>>>>> On 09/01/2026 09:19, Jan Beulich wrote:
>>>>>> On 31.12.2025 00:05, Matthieu Longo wrote:
>>>>>>> --- /dev/null
>>>>>>> +++ b/gas/testsuite/gas/gnu-attributes/oav2-failures-1.l
>>>>>>> @@ -0,0 +1,44 @@
>>>>>>> +.*: Assembler messages:
>>>>>>> +.*: Error: declaration of an attribute outside the scope of an attribute subsection
>>>>>>> +.*: Error: attribute 1 cannot be redefined
>>>>>>> +.*: Error: unexpected value -1, expected `unsigned integer' instead
>>>>>>> +.*: Error: could not parse attribute tag
>>>>>>> +.*: Error: unknown identifier 'Tag_Unknown' in this context
>>>>>>> +.*: Error: could not parse attribute tag
>>>>>>> +.*: Error: unknown identifier 'Tag_Unknown' in this context
>>>>>>> +.*: Error: could not parse attribute tag
>>>>>>> +.*: Error: unexpected `string' "plop", expected `unsigned integer' instead
>>>>>>> +.*: Error: could not parse attribute value
>>>>>>> +.*: Error: unexpected value -1, expected `unsigned integer' instead
>>>>>>> +.*: Error: could not parse attribute value
>>>>>>> +.*: Error: unexpected `string' "foo", expected `unsigned integer' instead
>>>>>>> +.*: Error: could not parse attribute value
>>>>>>> +.*: Error: unexpected integer 1, expected `string' instead
>>>>>>> +.*: Error: could not parse attribute value
>>>>>>> +.*: Error: attribute 4 cannot be redefined
>>>>>>> +.*: Error: comprehension and encoding of a subsection cannot be omitted on the first declaration
>>>>>>> +.*: Error: incompatible redeclaration of subsection vendor_1_subsection_3
>>>>>>> +.*:  Info: previous declaration had properties: comprehension=required, encoding=NTBS
>>>>>>> +.*: Error: incompatible redeclaration of subsection vendor_1_subsection_3
>>>>>>> +.*:  Info: previous declaration had properties: comprehension=required, encoding=NTBS
>>>>>>> +.*: Error: incompatible redeclaration of subsection vendor_1_subsection_3
>>>>>>> +.*:  Info: previous declaration had properties: comprehension=required, encoding=NTBS
>>>>>>> +.*: Error: unknown identifier 'ntbs' in this context
>>>>>>> +.*: Error: unknown identifier 'uleb128' in this context
>>>>>>> +.*: Error: expression '.vendor' does not resolve to an integer literal
>>>>>>> +.*: Error: fell back to integer literal extraction from expression, but expected `identifier' instead
>>>>>>> +.*: Error: expected <subsection_name>, <comprehension>, <encoding>
>>>>>>> +.*: Error: unknown identifier 'uleb128' in this context
>>>>>>> +.*: Error: unknown identifier 'optial' in this context
>>>>>>> +.*: Error: unknown identifier 'ul128' in this context
>>>>>>> +.*: Error: invalid value 2, expected values for <comprehension> are 0 \(=`required'\) or 1 \(=`optional'\)
>>>>>>> +.*: Error: invalid value 2, expected values for <encoding> are 0 \(=`ULEB128'\) or 1 \(=`NTBS'\)
>>>>
>>>> To reply to your response further down, I need to start here: These two
>>>> correspond to
>>>>
>>>>     .gnu_subsection vendor_1_subsection_4, 2, 1
>>>>     .gnu_subsection vendor_1_subsection_4, 1, 2
>>>>
>>>> afaict. Subsequent to it there are 2 sets of 4 directives in the source,
>>>> which would mean a total of 8 more error messages. Yet ...
>>>>
>>>>>>> +.*: Error: unexpected comma before parameter 2
>>>>>>> +.*: Error: junk at end of line, first unrecognized character is `,'
>>>>>>> +.*: Error: unexpected comma before parameter 1
>>>>>>> +.*: Error: missing comma after parameter 2
>>>>>>> +.*: Error: unexpected comma before parameter 2
>>>>>>> +.*: Error: junk at end of line, first unrecognized character is `,'
>>>>>>> +.*: Error: unexpected comma before parameter 1
>>>>>>> +.*: Error: junk at end of line, first unrecognized character is `1'
>>>>>>> +.*: Error: attribute 1 cannot be redefined
>>>>
>>>> ... there are 9 here.
>>>>
>>>> That's just one excess diagnostic (apparently from the last line in the
>>>> source)
>>>
>>> This last error is emitted because the junks at the end of line didn't prevent the parsing of the attribute from succeeding.
>>> So then we try to record the parsed attribute.
>>
>> But why? The line had an error; nothing needs generating / recording for
>> it.
> 
> demand_empty_rest_of_line() does not return any error code if junk is found.
> Consequently, the rest of the code cannot know if an error occurred.

Hmm, yes, so ...

>>>>>> Further many of the "junk at end of line" look to be secondary errors. Ideally
>>>>>> these would be avoided altogether (as a rule of thumb there should be just one
>>>>>> diagnostic per statement; see a respective comment I mad on an earlier patch),
>>>>>> but if that's not feasible for some reason, then their presence is entirely
>>>>>> irrelevant in this test, I would say.
>>>>>
>>>>> Each of those "junk at end of line" and "unexpected/missing comma" errors corresponds to one assembly line, and are not multiple errors generated on the same line.
>>>>
>>>> But then why is it once "unexpected comma" and once "junk at end of line, first
>>>> unrecognized character is `,'"? An excess comma generally indicates a subsequent
>>>> (possibly empty) argument. Imo excess commas should yield "too many arguments".
>>>>
>>>> Whether empty arguments really are to be considered an error is harder to tell:
>>>> Note how e.g. get_absolute_expression() treats <nothing> as 0. I don't consider
>>>> this to be the best of all possible behaviors, yet consistency throughout the
>>>> assembler is a relevant criteria to consider.
>>>
>>> What about this output ? Would it be less confusing ?
>>>
>>> .*: Error: syntax error, comma not expected here
>>> .*: Error: junk at end of line, first unrecognized character is `,'
>>> .*: Error: syntax error, comma not expected here
>>> .*: Error: syntax error, comma missing here
>>> .*: Error: syntax error, comma not expected here
>>> .*: Error: junk at end of line, first unrecognized character is `,'
>>> .*: Error: syntax error, comma not expected here
>>> .*: Error: junk at end of line, first unrecognized character is `1'
>>> .*: Error: attribute '1' cannot be redefined
>>
>> Yes, this is a little better. Still I'm not overly happy with it, as it still
>> doesn't work in terms of excess / missing arguments. Excess arguments are okay
>> to be "junk at end of line". That, however, also covers excess commas, i.e.
>> I'd expect the same "junk at end of line" wherever above has "comma not
>> expected here". A missing comma is one of two things: Either there's something
>> else there (again "junk at end of line"), or there's nothing there ("too few
>> arguments).
> 
> Should I understand from your comment that the current result is acceptable even if not perfect ?

... yes.

Jan