/* DWARF 2 support.
- Copyright 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
- 2004, 2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
+ Copyright 1994-2013 Free Software Foundation, Inc.
Adapted from gdb/dwarf2read.c by Gavin Koch of Cygnus Solutions
(gavin@cygnus.com).
asection *sec;
bfd_byte *sec_info_ptr;
+ /* Support for alternate debug info sections created by the DWZ utility:
+ This includes a pointer to an alternate bfd which contains *extra*,
+ possibly duplicate debug sections, and pointers to the loaded
+ .debug_str and .debug_info sections from this bfd. */
+ bfd * alt_bfd_ptr;
+ bfd_byte * alt_dwarf_str_buffer;
+ bfd_size_type alt_dwarf_str_size;
+ bfd_byte * alt_dwarf_info_buffer;
+ bfd_size_type alt_dwarf_info_size;
+
/* A pointer to the memory block allocated for info_ptr. Neither
info_ptr nor sec_info_ptr are guaranteed to stay pointing to the
beginning of the malloc block. This is used only to free the
{ ".debug_aranges", ".zdebug_aranges" },
{ ".debug_frame", ".zdebug_frame" },
{ ".debug_info", ".zdebug_info" },
+ { ".debug_info", ".zdebug_info" },
{ ".debug_line", ".zdebug_line" },
{ ".debug_loc", ".zdebug_loc" },
{ ".debug_macinfo", ".zdebug_macinfo" },
{ ".debug_static_func", ".zdebug_static_func" },
{ ".debug_static_vars", ".zdebug_static_vars" },
{ ".debug_str", ".zdebug_str", },
+ { ".debug_str", ".zdebug_str", },
{ ".debug_types", ".zdebug_types" },
/* GNU DWARF 1 extensions */
{ ".debug_sfnames", ".zdebug_sfnames" },
{ NULL, NULL },
};
+/* NB/ Numbers in this enum must match up with indicies
+ into the dwarf_debug_sections[] array above. */
enum dwarf_debug_section_enum
{
debug_abbrev = 0,
debug_aranges,
debug_frame,
debug_info,
+ debug_info_alt,
debug_line,
debug_loc,
debug_macinfo,
debug_static_func,
debug_static_vars,
debug_str,
+ debug_str_alt,
debug_types,
debug_sfnames,
debug_srcinfo,
asection *msec;
const char *section_name = sec->uncompressed_name;
- /* read_section is a noop if the section has already been read. */
- if (!*section_buffer)
+ /* The section may have already been read. */
+ if (*section_buffer == NULL)
{
msec = bfd_get_section_by_name (abfd, section_name);
if (! msec)
return str;
}
+/* Like read_indirect_string but uses a .debug_str located in
+ an alternate filepointed to by the .gnu_debuglink section.
+ Used to impement DW_FORM_GNU_strp_alt. */
+
+static char *
+read_alt_indirect_string (struct comp_unit * unit,
+ bfd_byte * buf,
+ unsigned int * bytes_read_ptr)
+{
+ bfd_uint64_t offset;
+ struct dwarf2_debug *stash = unit->stash;
+ char *str;
+
+ if (unit->offset_size == 4)
+ offset = read_4_bytes (unit->abfd, buf);
+ else
+ offset = read_8_bytes (unit->abfd, buf);
+
+ *bytes_read_ptr = unit->offset_size;
+
+ if (stash->alt_bfd_ptr == NULL)
+ {
+ bfd * debug_bfd;
+ char * debug_filename = bfd_follow_gnu_debugaltlink (unit->abfd, DEBUGDIR);
+
+ if (debug_filename == NULL)
+ return NULL;
+
+ if ((debug_bfd = bfd_openr (debug_filename, NULL)) == NULL
+ || ! bfd_check_format (debug_bfd, bfd_object))
+ {
+ if (debug_bfd)
+ bfd_close (debug_bfd);
+
+ /* FIXME: Should we report our failure to follow the debuglink ? */
+ free (debug_filename);
+ return NULL;
+ }
+ stash->alt_bfd_ptr = debug_bfd;
+ }
+
+ if (! read_section (unit->stash->alt_bfd_ptr,
+ stash->debug_sections + debug_str_alt,
+ NULL, /* FIXME: Do we need to load alternate symbols ? */
+ offset,
+ &stash->alt_dwarf_str_buffer,
+ &stash->alt_dwarf_str_size))
+ return NULL;
+
+ str = (char *) stash->alt_dwarf_str_buffer + offset;
+ if (*str == '\0')
+ return NULL;
+
+ return str;
+}
+
+/* Resolve an alternate reference from UNIT at OFFSET.
+ Returns a pointer into the loaded alternate CU upon success
+ or NULL upon failure. */
+
+static bfd_byte *
+read_alt_indirect_ref (struct comp_unit * unit,
+ bfd_uint64_t offset)
+{
+ struct dwarf2_debug *stash = unit->stash;
+
+ if (stash->alt_bfd_ptr == NULL)
+ {
+ bfd * debug_bfd;
+ char * debug_filename = bfd_follow_gnu_debugaltlink (unit->abfd, DEBUGDIR);
+
+ if (debug_filename == NULL)
+ return FALSE;
+
+ if ((debug_bfd = bfd_openr (debug_filename, NULL)) == NULL
+ || ! bfd_check_format (debug_bfd, bfd_object))
+ {
+ if (debug_bfd)
+ bfd_close (debug_bfd);
+
+ /* FIXME: Should we report our failure to follow the debuglink ? */
+ free (debug_filename);
+ return NULL;
+ }
+ stash->alt_bfd_ptr = debug_bfd;
+ }
+
+ if (! read_section (unit->stash->alt_bfd_ptr,
+ stash->debug_sections + debug_info_alt,
+ NULL, /* FIXME: Do we need to load alternate symbols ? */
+ offset,
+ &stash->alt_dwarf_info_buffer,
+ &stash->alt_dwarf_info_size))
+ return NULL;
+
+ return stash->alt_dwarf_info_buffer + offset;
+}
+
static bfd_uint64_t
read_address (struct comp_unit *unit, bfd_byte *buf)
{
attr->u.val = read_address (unit, info_ptr);
info_ptr += unit->addr_size;
break;
+ case DW_FORM_GNU_ref_alt:
case DW_FORM_sec_offset:
if (unit->offset_size == 4)
attr->u.val = read_4_bytes (unit->abfd, info_ptr);
attr->u.str = read_indirect_string (unit, info_ptr, &bytes_read);
info_ptr += bytes_read;
break;
+ case DW_FORM_GNU_strp_alt:
+ attr->u.str = read_alt_indirect_string (unit, info_ptr, &bytes_read);
+ info_ptr += bytes_read;
+ break;
case DW_FORM_exprloc:
case DW_FORM_block:
amt = sizeof (struct dwarf_block);
info_ptr = read_attribute_value (attr, form, unit, info_ptr);
break;
default:
- (*_bfd_error_handler) (_("Dwarf Error: Invalid or unhandled FORM value: %u."),
+ (*_bfd_error_handler) (_("Dwarf Error: Invalid or unhandled FORM value: %#x."),
form);
bfd_set_error (bfd_error_bad_value);
return NULL;
return NULL;
}
-/* If ADDR is within TABLE set the output parameters and return TRUE,
- otherwise return FALSE. The output parameters, FILENAME_PTR and
- LINENUMBER_PTR, are pointers to the objects to be filled in. */
+/* If ADDR is within TABLE set the output parameters and return the
+ range of addresses covered by the entry used to fill them out.
+ Otherwise set * FILENAME_PTR to NULL and return 0.
+ The parameters FILENAME_PTR, LINENUMBER_PTR and DISCRIMINATOR_PTR
+ are pointers to the objects to be filled in. */
-static bfd_boolean
+static bfd_vma
lookup_address_in_line_info_table (struct line_info_table *table,
bfd_vma addr,
const char **filename_ptr,
*linenumber_ptr = each_line->line;
if (discriminator_ptr)
*discriminator_ptr = each_line->discriminator;
- return TRUE;
+ return seq->last_line->address - seq->low_pc;
}
}
*filename_ptr = NULL;
- return FALSE;
+ return 0;
}
/* Read in the .debug_ranges section for future reference. */
/* Function table functions. */
-/* If ADDR is within TABLE, set FUNCTIONNAME_PTR, and return TRUE.
- Note that we need to find the function that has the smallest
- range that contains ADDR, to handle inlined functions without
- depending upon them being ordered in TABLE by increasing range. */
+/* If ADDR is within UNIT's function tables, set FUNCTIONNAME_PTR, and return
+ TRUE. Note that we need to find the function that has the smallest range
+ that contains ADDR, to handle inlined functions without depending upon
+ them being ordered in TABLE by increasing range. */
static bfd_boolean
lookup_address_in_function_table (struct comp_unit *unit,
struct abbrev_info *abbrev;
bfd_uint64_t die_ref = attr_ptr->u.val;
struct attribute attr;
- char *name = 0;
+ char *name = NULL;
/* DW_FORM_ref_addr can reference an entry in a different CU. It
is an offset from the .debug_info section, not the current CU. */
info_ptr = unit->sec_info_ptr + die_ref;
}
+ else if (attr_ptr->form == DW_FORM_GNU_ref_alt)
+ {
+ info_ptr = read_alt_indirect_ref (unit, die_ref);
+ if (info_ptr == NULL)
+ {
+ (*_bfd_error_handler)
+ (_("Dwarf Error: Unable to read alt ref %u."), die_ref);
+ bfd_set_error (bfd_error_bad_value);
+ return name;
+ }
+ }
else
info_ptr = unit->info_ptr_unit + die_ref;
+
abbrev_number = read_unsigned_leb128 (abfd, info_ptr, &bytes_read);
info_ptr += bytes_read;
FUNCTIONNAME_PTR, and LINENUMBER_PTR, are pointers to the objects
to be filled in.
- Return TRUE if UNIT contains ADDR, and no errors were encountered;
- FALSE otherwise. */
+ Returns the range of addresses covered by the entry that was used
+ to fill in *LINENUMBER_PTR or 0 if it was not filled in. */
-static bfd_boolean
+static bfd_vma
comp_unit_find_nearest_line (struct comp_unit *unit,
bfd_vma addr,
const char **filename_ptr,
unsigned int *discriminator_ptr,
struct dwarf2_debug *stash)
{
- bfd_boolean line_p;
bfd_boolean func_p;
struct funcinfo *function;
&function, functionname_ptr);
if (func_p && (function->tag == DW_TAG_inlined_subroutine))
stash->inliner_chain = function;
- line_p = lookup_address_in_line_info_table (unit->line_table, addr,
- filename_ptr,
- linenumber_ptr,
- discriminator_ptr);
- return line_p || func_p;
+
+ return lookup_address_in_line_info_table (unit->line_table, addr,
+ filename_ptr,
+ linenumber_ptr,
+ discriminator_ptr);
}
/* Check to see if line info is already decoded in a comp_unit.
/* What address are we looking for? */
bfd_vma addr;
struct comp_unit* each;
- bfd_vma found = FALSE;
+ bfd_boolean found = FALSE;
bfd_boolean do_line;
*filename_ptr = NULL;
}
else
{
+ bfd_vma min_range = (bfd_vma) -1;
+ const char * local_filename = NULL;
+ const char * local_functionname = NULL;
+ unsigned int local_linenumber = 0;
+ unsigned int local_discriminator = 0;
+
for (each = stash->all_comp_units; each; each = each->next_unit)
{
+ bfd_vma range = (bfd_vma) -1;
+
found = ((each->arange.high == 0
|| comp_unit_contains_address (each, addr))
- && comp_unit_find_nearest_line (each, addr,
- filename_ptr,
- functionname_ptr,
- linenumber_ptr,
- discriminator_ptr,
- stash));
+ && (range = comp_unit_find_nearest_line (each, addr,
+ & local_filename,
+ & local_functionname,
+ & local_linenumber,
+ & local_discriminator,
+ stash)) != 0);
if (found)
- goto done;
+ {
+ /* PRs 15935 15994: Bogus debug information may have provided us
+ with an erroneous match. We attempt to counter this by
+ selecting the match that has the smallest address range
+ associated with it. (We are assuming that corrupt debug info
+ will tend to result in extra large address ranges rather than
+ extra small ranges).
+
+ This does mean that we scan through all of the CUs associated
+ with the bfd each time this function is called. But this does
+ have the benefit of producing consistent results every time the
+ function is called. */
+ if (range <= min_range)
+ {
+ if (filename_ptr && local_filename)
+ * filename_ptr = local_filename;
+ if (functionname_ptr && local_functionname)
+ * functionname_ptr = local_functionname;
+ if (discriminator_ptr && local_discriminator)
+ * discriminator_ptr = local_discriminator;
+ if (local_linenumber)
+ * linenumber_ptr = local_linenumber;
+ min_range = range;
+ }
+ }
+ }
+
+ if (* linenumber_ptr)
+ {
+ found = TRUE;
+ goto done;
}
}
functionname_ptr,
linenumber_ptr,
discriminator_ptr,
- stash));
+ stash)) > 0;
if ((bfd_vma) (stash->info_ptr - stash->sec_info_ptr)
== stash->sec->size)
free (stash->info_ptr_memory);
if (stash->close_on_cleanup)
bfd_close (stash->bfd_ptr);
+ if (stash->alt_dwarf_str_buffer)
+ free (stash->alt_dwarf_str_buffer);
+ if (stash->alt_dwarf_info_buffer)
+ free (stash->alt_dwarf_info_buffer);
+ if (stash->alt_bfd_ptr)
+ bfd_close (stash->alt_bfd_ptr);
}