[Bug c++/116913] [15 regression] ICE when building firefox-130.0.1 (tree check: expected var_decl or function_decl or field_decl or type_decl or concept_decl or template_decl, have using_decl in cp_parser_alias_declaration, at cp/parser.cc:22826)

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116913

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
This comes from an unified source that is #include all of the C++ code into one
main source file.

This is why this odd pattern shows up; I doubt it will show up in code without
this kind of unification.

That is:
header:
```
namespace ns {
  typedef int t;
}
```

source1:
```
using ns::t;
...
```

source2:
```
using t = ns::t;
````


unified source includes both source1 and source2.