Re: patch for dwarf2read.c

[Gaius Mulley <gaius at glam dot ac dot uk>]

Gaius Mulley <gaius@glam.ac.uk> writes:

> Hi,
> 
> here is a patch for dwarf2read.c which fixes a cyclic recursive bug
> when gdb is asked to resolve the following Modula-2 procedure type:
> 
>   ScanClass = (padding, valid, invalid, terminator);
>   ScanState = PROCEDURE (CHAR, VAR ScanClass, VAR ScanState);
> 
> when compiled by gm2.
> 
> regards,
> Gaius

ps. oops I forgot to say that no more regression tests fail if the
patch is applied on the x86_64 Debian GNU/Linux platform


> 
> 
> 
> --- orig/src/gdb/dwarf2read.c	2008-11-16 23:51:59.000000000 +0000
> +++ modified/src/gdb/dwarf2read.c	2008-11-16 23:47:51.000000000 +0000
> @@ -769,6 +769,9 @@
>  static void add_partial_enumeration (struct partial_die_info *enum_pdi,
>  				     struct dwarf2_cu *cu);
>  
> +static void add_partial_subroutine_type (struct partial_die_info *enum_pdi,
> +					 struct dwarf2_cu *cu);
> +
>  static void add_partial_subprogram (struct partial_die_info *pdi,
>  				    CORE_ADDR *lowpc, CORE_ADDR *highpc,
>  				    struct dwarf2_cu *cu);
> @@ -2287,6 +2290,32 @@
>      }
>  }
>  
> +/* Read a partial die corresponding to a subroutine type.  */
> +
> +static void
> +add_partial_subroutine_type (struct partial_die_info *subroutine_type_pdi,
> +			     struct dwarf2_cu *cu)
> +{
> +  struct objfile *objfile = cu->objfile;
> +  bfd *abfd = objfile->obfd;
> +  struct partial_die_info *pdi;
> +
> +  if (subroutine_type_pdi->name != NULL)
> +    add_partial_symbol (subroutine_type_pdi, cu);
> +
> +  pdi = subroutine_type_pdi->die_child;
> +  while (pdi)
> +    {
> +      if (pdi->tag != DW_TAG_formal_parameter
> +	  || pdi->tag != DW_TAG_unspecified_parameters
> +	  || pdi->name == NULL)
> +	complaint (&symfile_complaints, _("malformed parameter DIE ignored"));
> +      else
> +	add_partial_symbol (pdi, cu);
> +      pdi = pdi->die_sibling;
> +    }
> +}
> +
>  /* Read the initial uleb128 in the die at INFO_PTR in compilation unit CU.
>     Return the corresponding abbrev, or NULL if the number is zero (indicating
>     an empty DIE).  In either case *BYTES_READ will be set to the length of
> @@ -4946,7 +4975,16 @@
>       the default value DW_CC_normal.  */
>    attr = dwarf2_attr (die, DW_AT_calling_convention, cu);
>    TYPE_CALLING_CONVENTION (ftype) = attr ? DW_UNSND (attr) : DW_CC_normal;
> -  
> +
> +  TYPE_STUB_SUPPORTED (ftype) = 1;
> +  if (die_is_declaration (die, cu))
> +    TYPE_STUB (ftype) = 1;
> +
> +  /* We need to add the type field to the die immediately so we don't
> +     infinitely recurse when dealing with parameters declared as
> +     the same subroutine type. */
> +  set_die_type (die, ftype, cu);
> +
>    if (die->child != NULL)
>      {
>        struct die_info *child_die;
> @@ -4993,7 +5031,7 @@
>  	}
>      }
>  
> -  return set_die_type (die, ftype, cu);
> +  return ftype;
>  }
>  
>  static struct type *
> @@ -5598,8 +5636,8 @@
>      case DW_TAG_ptr_to_member_type:
>      case DW_TAG_set_type:
>      case DW_TAG_string_type:
> -    case DW_TAG_subroutine_type:
>  #endif
> +    case DW_TAG_subroutine_type:
>      case DW_TAG_base_type:
>      case DW_TAG_class_type:
>      case DW_TAG_interface_type: