[PATCH] D132900: [DWARF] Fix infinite recursion in Type Printer.

[Alexander Yermolovich via Phabricator via llvm-commits]

ayermolo added inline comments.


================
Comment at: llvm/lib/DebugInfo/DWARF/DWARFTypePrinter.cpp:289-290
 void DWARFTypePrinter::appendQualifiedName(DWARFDie D) {
-  if (D)
+  if (D && !ScopelessDIEs.count(D.getTag()))
     appendScopes(D.getParent());
+
----------------
dblaikie wrote:
> Might be inclined to use a switch here, rather than a set lookup - and it's probably easier to make a positive list of the things that are scoped than those that aren't.
Unfortunately this doesn't work for:

```
class codecvt_base
{
  public:
    enum result {
      ok
    };
};

class __codecvt_abstract_base
    : public codecvt_base
{
    public:
      result out(const wchar_t* __from) const {
      return result::ok;
      }
    };

    class codecvt
    : public __codecvt_abstract_base{};

    inline bool
    __str_codecvt_out()
    {
      using _Codecvt = codecvt;
      using _ConvFn = codecvt_base::result
    (_Codecvt::*)(const wchar_t*) const;
      _ConvFn __fn = &codecvt::out;
      return true;
    }

bool test() {
    return __str_codecvt_out();
}
```

It prints out this before eventually crashing.
0x00000133:       DW_TAG_formal_parameter [8]   (0x00000126)
                    DW_AT_type [DW_FORM_ref4] (cu + 0x0138 => {0x00000138} "codecvt_base::result (codecvt_base::result (codecvt_base::result (codecvt_base::result (codecvt_base::result (codecvt_base::result (codecvt_base::result (codecvt_base::result (codecvt_base::result (codecvt_base::result (::codecvt_base::result (::const _Codecvt *::codecvt_base::result (::const _Codecvt *::codecvt_base::result (::const _Codecvt *::codecvt_base::result (::const _Codecvt *::codecvt_base::result (::const _Codecvt *::codecvt_base::result (::const _Codecvt *::codecvt_base::result (::const _Codecvt *::codecvt_base::result (::const _Codecvt *::codecvt_base::result (::const _Codecvt *::codecvt_base::result (::const _Codecvt *")


Maybe better approach is to apply this allow list approach to DWARFTypePrinter::appendScopes? So it will return unless it's one of those TAGs.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D132900/new/

https://reviews.llvm.org/D132900