Re: [PATCH] Add a character size parameter to c_strlen/get_range_strlen

[Jeff Law <law at redhat dot com>]

On 08/20/2018 04:16 PM, Joseph Myers wrote:
> On Fri, 17 Aug 2018, Jeff Law wrote:
> 
>>> WCHAR_TYPE_SIZE is wrong because it doesn't account for flag_short_wchar.  
>>> As far as I can see only ada/gcc-interface/targtyps.c uses WCHAR_TYPE_SIZE 
>>> now.  TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT is what should be 
>>> used.
>> But that's specific to the c-family front-ends.
>>
>> There's MODIFIED_WCHAR_TYPE which is ultimately used to build
>> wchar_type_node for the c-family front-ends.  Maybe we could construct
>> something from that.
> 
> If you do that, probably you want to move 
> fortran/trans-types.c:get_typenode_from_name (which converts the strings 
> used in target macros such as WCHAR_TYPE to the corresponding types) into 
> generic code.
I think we ultimately have to go down that path.  Or we have to make the
wchar types language independent.

My initial fooling around does something like this:

  count_by = 1;
  if (dir.specifier == 'S' || dir.modifier == FMT_LEN_l)
    {
      tree node = get_identifier (MODIFIED_WCHAR_TYPE);
      if (node)
        count_by = TYPE_PRECISION (TREE_TYPE (node)) / BITS_PER_UNIT
    }

Of course, I still have to fire up tests on AIX to know if that, or a
variant using get_typenode_from_name will DTRT.

Jeff