[PATCH] document IntegerRange in internals manual

[Martin Sebor]

On 07/11/2017 07:32 AM, Martin Liška wrote:
> On 07/10/2017 05:08 PM, Martin Sebor wrote:
>> On 07/10/2017 02:35 AM, Martin Liška wrote:
>>> On 07/07/2017 09:20 PM, Martin Sebor wrote:
>>>> A conflict in my patch for bug 81345 made me notice that r249734
>>>> recently added a new option property, IntegerRange.  The change
>>>> below adds brief documentation of the property to the manual.
>>>>
>>>> Martin, can you please check to make sure I didn't miss anything?
>>>>
>>>> Btw., while experimenting with the property I noticed that there
>>>> is no error when option that specifies IntegerRange is set in
>>>> the .opt file to a value outside that range.  Would it be hard
>>>> to add some checks the the awk scripts to validate that the
>>>> argument values are in the range?  It might help avoid bugs
>>>> similar to 81345).
>>>
>>> Sure, please take a look at attached patch. Can you please test it?
>>
>> The detection works fine for the Init problem (thanks!) but it
>> doesn't catch the out-of-range initializer in LangEnabledBy(C,
>> Wall, 2, 0) or in Alias(Wfoobar=, 1, 0).  I don't know enough
>> about the option scripts yet to gauge how difficult handling
>> these might be.  Do you have any idea?  If you think it's
>> doable but outside the scope of this tweak let me know and I'll
>> open a bug for it to help us remember to handle it at some point
>> too.
>
> Well, it's definitely doable, but doing that in the current awk script
> is quite cumbersome.
> I would prefer to have the option generation rewritten e.g. in Python
> where current awk
> script is not nice to reuse an already parsed information. More
> class-oriented approach would
> be desired here.
>
> Please create a PR, I maybe rewrite it in future if we can benefit from
> that.

I created bug 81397 for all these problems.

> Are you interested in the current patch that handles 'Init' directive to
> go in?

Yes please, thank you!

Martin

>
> Martin
>
>>
>>>>
>>>> By the way of an example, the following invalid specification
>>>> is accepted but then causes errors when GCC runs.
>>>>
>>>> Wfoobar
>>>> C ObjC C++ ObjC++ Warning Alias(Wfoobar=, 1, 0)
>>>>
>>>> Wfoobar=
>>>> C ObjC C++ ObjC++ Joined RejectNegative UInteger Var(warn_foobar)
>>>> Warning LangEnabledBy(C ObjC C++ ObjC++, Wall, 2, 0) Init (7)
>>>> IntegerRange(3, 5)
>>>
>>> Here one needs to have 'Init (7)' without space!
>>
>> Ugh.  I only recently realized this but keep forgetting.  It
>> seems like another unnecessary trap that would be nice to fix
>> at some point.
>>
>> Thanks
>> Martin
>>
>>>
>>>>
>>>> Martin
>>>>
>>>> diff --git a/gcc/doc/options.texi b/gcc/doc/options.texi
>>>> index 3b68aab..af56e9f 100644
>>>> --- a/gcc/doc/options.texi
>>>> +++ b/gcc/doc/options.texi
>>>> @@ -264,6 +264,12 @@ option handler.  @code{UInteger} should also be
>>>> used on options like
>>>>  @code{-falign-loops}=@var{n} are supported to make sure the saved
>>>>  options are given a full integer.
>>>>
>>>> +@item IntegerRange(@var{min}, @var{max})
>>>> +The option's integer argument is expected to be in the range specified
>>>> +by @var{min} and @var{max}, inclusive.  The option parser will check
>>>> +and reject option arguments that are outside the range before passing
>>>> +it to the relevant option handler.
>>>
>>> LGTM, thanks for the documentation entry.
>>>
>>> Martin
>>>
>>>> +
>>>>  @item ToLower
>>>>  The option's argument should be converted to lowercase as part of
>>>>  putting it in canonical form, and before comparing with the strings
>>>
>>
>