# DWARF Generation on D compilers

- DMD lacks information about `DW_AT_decl_file`, `DW_AT_decl_line` and
  `DW_AT_decl_column` on some tags.
- LDC lacks information about `DW_AT_decl_column`.
- LDC generates artificial DWARF variables and don't properly mark then as
  `DW_AT_artificial`.

## Types

- GDC produces an error on LLDB:
  ```
  error: need to add support for DW_TAG_base_type 'dchar' encoded with DW_ATE = 0x8, bit_size = 32
  ```

- DMD for some reason, unknown to my current compiler knowledge, is generating
  `_Bool` type name for `bool` types.

## Enumerations

- DMD has a bug with `DW_TAG_enumerator`. Currently that information is not
  being generated.

## Arrays

- No D compiler generates correct DWARF tags to represent dynamic arrays. They
  should use `DW_TAG_array_type` with `DW_TAG_subrange_type` and reference the
  size of it using `DW_AT_count`/`DW_AT_upper_bound` variable address or
  manually dereference a stack register, containing the size. This approach is
  used by C compilers when dealing with VLAs.

### Normal Arrays

- Every D compiler except DMD handles normal array type names with fully
  qualified names. I already pushed a fix to this.
- Every D compiler writes array DWARF information as a struct with length and
  ptr fields.

- No D compiler generates special DWARF tags when dealing with string arrays.

### Associative Arrays

- DMD has a bug for associative arrays with array types, reporting the wrong
  type in the name.

  For an `int[string]` it reports `_AArray_ucent_int` For an `string[int]` it
  reports `_AArray_int_ucent`

- Every D compiler except DMD handles associative array types with fully
  qualified names.

- Associative array struct is not accessible on any D compiler

### Interfaces

- GDC uses `DW_TAG_interface_type` tags including `DW_AT_containing_type`
  pointing to themselves as part of GNU extensions to DWARF, triggering an
  error on LLDB. This tag is not part of the DWARF structure for interfaces.