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Re: [patch] Fix DW_AT_lower_bound DWARF-4+ defaults
On Thu, 26 Apr 2012 17:43:34 +0200, Tom Tromey wrote:
> I think the nicest thing would be to pick the DWARF 4 defaults, and
> complain for other versions.
OK.
Thanks,
Jan
gdb/
2012-04-26 Jan Kratochvil <jan.kratochvil@redhat.com>
Fix DW_AT_lower_bound defaults for DWARF-4+.
* dwarf2read.c (read_subrange_type): Remove initialization of low and
high. New variable low_default_is_valid. Implement DWARF-4+
DW_AT_lower_bound defaults. Print complaint for DW_AT_lower_bound with
no default by the DWARF standard.
diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index bd2d6f2..99bba9f 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -9086,8 +9086,8 @@ read_subrange_type (struct die_info *die, struct dwarf2_cu *cu)
struct type *base_type;
struct type *range_type;
struct attribute *attr;
- LONGEST low = 0;
- LONGEST high = -1;
+ LONGEST low, high;
+ int low_default_is_valid;
char *name;
LONGEST negative_mask;
@@ -9100,10 +9100,35 @@ read_subrange_type (struct die_info *die, struct dwarf2_cu *cu)
if (range_type)
return range_type;
- if (cu->language == language_fortran)
+ /* Set LOW_DEFAULT_IS_VALID if current language and DWARF version allow
+ omitting DW_AT_lower_bound. */
+ switch (cu->language)
{
- /* FORTRAN implies a lower bound of 1, if not given. */
+ case language_c:
+ case language_cplus:
+ low = 0;
+ low_default_is_valid = 1;
+ break;
+ case language_fortran:
+ low = 1;
+ low_default_is_valid = 1;
+ break;
+ case language_d:
+ case language_java:
+ case language_objc:
+ low = 0;
+ low_default_is_valid = (cu->header.version >= 4);
+ break;
+ case language_ada:
+ case language_m2:
+ case language_pascal:
low = 1;
+ low_default_is_valid = (cu->header.version >= 4);
+ break;
+ default:
+ low = 0;
+ low_default_is_valid = 0;
+ break;
}
/* FIXME: For variable sized arrays either of these could be
@@ -9111,7 +9136,11 @@ read_subrange_type (struct die_info *die, struct dwarf2_cu *cu)
but we don't know how to handle it. */
attr = dwarf2_attr (die, DW_AT_lower_bound, cu);
if (attr)
- low = dwarf2_get_attr_constant_value (attr, 0);
+ low = dwarf2_get_attr_constant_value (attr, low);
+ else if (!low_default_is_valid)
+ complaint (&symfile_complaints, _("Missing DW_AT_lower_bound "
+ "- DIE at 0x%x [in module %s]"),
+ die->offset.sect_off, cu->objfile->name);
attr = dwarf2_attr (die, DW_AT_upper_bound, cu);
if (attr)