[patch, Fortran] Fix PR 82372

[Thomas Koenig]

Hi Steve,

>> the attached patch displays an error for characters which are
>> outside the normal Fortran character set, and includes a hex
> 
> If this              ^^^^^^^^^^^^^^^^^^^^^

> corresponds to this statement,
> 
>>   
>> +char valid_chars[] =
>> +  "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
>> +  "=+*-/^%[].,\n\t\r'\"();:<>_!$&0123456789";
> 
> then this is not correct.

You're correct, my statement above was misleading.

What I meant was the characters which can occur inside
normal Fortran syntax, plus a few more places, such as an
!$OMP statement.

>From F2003, letters, digits,
> underscore, and special characters (see Table 3.1) are
> members of the Fortran character set.  Your string includes
> \n, \t, and \r, which are not in the Fortran character set.
\t we warn about separetely. \n and \r can occur during parsing,
so we should not warn about them,

> Your string is missing \, {, }, ~, `, |, #, and @.

AFAIK, none of these characters can come up in an normal Fortran
statement except for a comment, string, format or continuation
character in fixed form.

Regards

	Thomas