[Bug c/68162] [5/6 Regression] Incompatible pointer type using a typedef

["joseph at codesourcery dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68162

--- Comment #8 from joseph at codesourcery dot com <joseph at codesourcery dot com> ---
I don't know what DWARF semantics are meant to be, but the language 
semantics are definitely that in C array types are always unqualified, 
whereas in C++, while the qualifiers still apply to the element type, the 
array type is also considered qualified for most/all purposes.

> When I just not do that main variant punning here I get
> 
>  <1><60>: Abbrev Number: 10 (DW_TAG_variable)
>     <61>   DW_AT_name        : (indirect string, offset: 0x7b): harry
>     <65>   DW_AT_decl_file   : 1
>     <66>   DW_AT_decl_line   : 5
>     <67>   DW_AT_type        : <0x75>
> ...
>  <1><75>: Abbrev Number: 6 (DW_TAG_const_type)
>     <76>   DW_AT_type        : <0x49>
>  <1><49>: Abbrev Number: 7 (DW_TAG_array_type)
>     <4a>   DW_AT_type        : <0x39>
>     <4e>   DW_AT_sibling     : <0x59>
>  <1><39>: Abbrev Number: 5 (DW_TAG_typedef)
>     <3a>   DW_AT_name        : (indirect string, offset: 0x0): Harry_t
>     <3e>   DW_AT_decl_file   : 1
>     <3f>   DW_AT_decl_line   : 4
>     <40>   DW_AT_type        : <0x44>
> 
> instead.  Not sure about that "extra" const qualifier on the array type
> though.

Does the extra qualifier come from decl_quals extracting qualifiers from a 
decl to combine with those for the type?  My guess would be that such code 
for extracting qualifiers is a legacy of when, a long time ago (before 
<https://gcc.gnu.org/ml/gcc-patches/2001-06/msg00498.html>), the types of 
decls in the C and C++ front ends did not include top-level qualifiers, 
and so should be obsolete now.