Re: build broken by dwarf2read.c changes

Keith Seitz
2011-10-11T23:23:36Z

On 10/11/2011 03:55 PM, David Miller wrote:
>
> The recent commit which claims to rearrange conditional logic
> in partial_die_parent_scope() does a lot of other things to
> dwarf2read.c

$ cvs log dwarf2read.c
[snip]
revision 1.569
date: 2011/10/11 19:19:07; author: sterling; state: Exp; lines: +52 -408
gdb/ChangeLog
2011-10-11 Sterling Augustine <saugustine@google.com>

* dwarf2read.c (partial_die_parent_scope): Rearrange conditional
logic.

gdb/testsuite/ChangeLog
2011-10-11 Sterling Augustine <saugustine@google.com>

* gdb.cp/Makefile.in: Add namespace-enum test.
* gdb.cp/namespace-enum.exp: New file.
* gdb.cp/namespace-enum.c: New file.
* gdb.cp/namespace-enum-main.c: New file.
[snip]

$ cvs diff -r 1.568 -r 1.569 dwarf2read.c
Index: dwarf2read.c
===================================================================
RCS file: /cvs/src/src/gdb/dwarf2read.c,v
retrieving revision 1.568
retrieving revision 1.569
diff -u -p -r1.568 -r1.569
--- dwarf2read.c 9 Oct 2011 19:34:18 -0000 1.568
+++ dwarf2read.c 11 Oct 2011 19:19:07 -0000 1.569
@@ -407,9 +407,6 @@ struct dwarf2_cu
after all type information has been read. */
VEC (delayed_method_info) *method_list;

- /* To be copied to symtab->call_site_htab. */
- htab_t call_site_htab;
-
/* Mark used when releasing cached dies. */
unsigned int mark : 1;

@@ -1082,8 +1079,6 @@ static void read_func_scope (struct die_

static void read_lexical_block_scope (struct die_info *, struct
dwarf2_cu *);

-static void read_call_site_scope (struct die_info *die, struct
dwarf2_cu *cu);
-
static int dwarf2_ranges_read (unsigned, CORE_ADDR *, CORE_ADDR *,
struct dwarf2_cu *, struct partial_symtab *);

@@ -2655,21 +2650,7 @@ dw2_find_symbol_file (struct objfile *ob

/* index_table is NULL if OBJF_READNOW. */
if (!dwarf2_per_objfile->index_table)
- {
- struct symtab *s;
-
- ALL_OBJFILE_SYMTABS (objfile, s)
- if (s->primary)
- {
- struct blockvector *bv = BLOCKVECTOR (s);
- const struct block *block = BLOCKVECTOR_BLOCK (bv, GLOBAL_BLOCK);
- struct symbol *sym = lookup_block_symbol (block, name, VAR_DOMAIN);
-
- if (sym)
- return sym->symtab->filename;
- }
- return NULL;
- }
+ return NULL;

if (!find_slot_in_mapped_hash (dwarf2_per_objfile->index_table,
name, &vec))
@@ -3897,7 +3878,10 @@ partial_die_parent_scope (struct partial
return NULL;
}

- if (parent->tag == DW_TAG_namespace
+ if (pdi->tag == DW_TAG_enumerator)
+ /* Enumerators should not get the name of the enumeration as a
prefix. */
+ parent->scope = grandparent_scope;
+ else if (parent->tag == DW_TAG_namespace
|| parent->tag == DW_TAG_module
|| parent->tag == DW_TAG_structure_type
|| parent->tag == DW_TAG_class_type
@@ -3912,9 +3896,6 @@ partial_die_parent_scope (struct partial
grandparent_scope,
parent->name, 0, cu);
}
- else if (parent->tag == DW_TAG_enumerator)
- /* Enumerators should not get the name of the enumeration as a
prefix. */
- parent->scope = grandparent_scope;
else
{
/* FIXME drow/2004-04-01: What should we be doing with
@@ -4804,8 +4785,6 @@ process_full_comp_unit (struct dwarf2_pe

if (gcc_4_minor >= 5)
symtab->epilogue_unwind_valid = 1;
-
- symtab->call_site_htab = cu->call_site_htab;
}

if (dwarf2_per_objfile->using_index)
@@ -4844,9 +4823,6 @@ process_die (struct die_info *die, struc
case DW_TAG_catch_block:
read_lexical_block_scope (die, cu);
break;
- case DW_TAG_GNU_call_site:
- read_call_site_scope (die, cu);
- break;
case DW_TAG_class_type:
case DW_TAG_interface_type:
case DW_TAG_structure_type:
@@ -6141,258 +6117,6 @@ read_lexical_block_scope (struct die_inf
using_directives = new->using_directives;
}

-/* Read in DW_TAG_GNU_call_site and insert it to CU->call_site_htab. */
-
-static void
-read_call_site_scope (struct die_info *die, struct dwarf2_cu *cu)
-{
- struct objfile *objfile = cu->objfile;
- struct gdbarch *gdbarch = get_objfile_arch (objfile);
- CORE_ADDR pc, baseaddr;
- struct attribute *attr;
- struct call_site *call_site, call_site_local;
- void **slot;
- int nparams;
- struct die_info *child_die;
-
- baseaddr = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));
-
- attr = dwarf2_attr (die, DW_AT_low_pc, cu);
- if (!attr)
- {
- complaint (&symfile_complaints,
- _("missing DW_AT_low_pc for DW_TAG_GNU_call_site "
- "DIE 0x%x [in module %s]"),
- die->offset, cu->objfile->name);
- return;
- }
- pc = DW_ADDR (attr) + baseaddr;
-
- if (cu->call_site_htab == NULL)
- cu->call_site_htab = htab_create_alloc_ex (16, core_addr_hash,
core_addr_eq,
- NULL, &objfile->objfile_obstack,
- hashtab_obstack_allocate, NULL);
- call_site_local.pc = pc;
- slot = htab_find_slot (cu->call_site_htab, &call_site_local, INSERT);
- if (*slot != NULL)
- {
- complaint (&symfile_complaints,
- _("Duplicate PC %s for DW_TAG_GNU_call_site "
- "DIE 0x%x [in module %s]"),
- paddress (gdbarch, pc), die->offset, cu->objfile->name);
- return;
- }
-
- /* Count parameters at the caller. */
-
- nparams = 0;
- for (child_die = die->child; child_die && child_die->tag;
- child_die = sibling_die (child_die))
- {
- if (child_die->tag != DW_TAG_GNU_call_site_parameter)
- {
- complaint (&symfile_complaints,
- _("Tag %d is not DW_TAG_GNU_call_site_parameter in "
- "DW_TAG_GNU_call_site child DIE 0x%x [in module %s]"),
- child_die->tag, child_die->offset, cu->objfile->name);
- continue;
- }
-
- nparams++;
- }
-
- call_site = obstack_alloc (&objfile->objfile_obstack,
- (sizeof (*call_site)
- + (sizeof (*call_site->parameter)
- * (nparams - 1))));
- *slot = call_site;
- memset (call_site, 0, sizeof (*call_site) - sizeof
(*call_site->parameter));
- call_site->pc = pc;
-
- if (dwarf2_flag_true_p (die, DW_AT_GNU_tail_call, cu))
- {
- struct die_info *func_die;
-
- /* Skip also over DW_TAG_inlined_subroutine. */
- for (func_die = die->parent;
- func_die && func_die->tag != DW_TAG_subprogram
- && func_die->tag != DW_TAG_subroutine_type;
- func_die = func_die->parent);
-
- /* DW_AT_GNU_all_call_sites is a superset
- of DW_AT_GNU_all_tail_call_sites. */
- if (func_die
- && !dwarf2_flag_true_p (func_die, DW_AT_GNU_all_call_sites, cu)
- && !dwarf2_flag_true_p (func_die, DW_AT_GNU_all_tail_call_sites, cu))
- {
- /* TYPE_TAIL_CALL_LIST is not interesting in functions where it is
- not complete. But keep CALL_SITE for look ups via call_site_htab,
- both the initial caller containing the real return address PC and
- the final callee containing the current PC of a chain of tail
- calls do not need to have the tail call list complete. But any
- function candidate for a virtual tail call frame searched via
- TYPE_TAIL_CALL_LIST must have the tail call list complete to be
- determined unambiguously. */
- }
- else
- {
- struct type *func_type = NULL;
-
- if (func_die)
- func_type = get_die_type (func_die, cu);
- if (func_type != NULL)
- {
- gdb_assert (TYPE_CODE (func_type) == TYPE_CODE_FUNC);
-
- /* Enlist this call site to the function. */
- call_site->tail_call_next = TYPE_TAIL_CALL_LIST (func_type);
- TYPE_TAIL_CALL_LIST (func_type) = call_site;
- }
- else
- complaint (&symfile_complaints,
- _("Cannot find function owning DW_TAG_GNU_call_site "
- "DIE 0x%x [in module %s]"),
- die->offset, cu->objfile->name);
- }
- }
-
- attr = dwarf2_attr (die, DW_AT_GNU_call_site_target, cu);
- if (attr == NULL)
- attr = dwarf2_attr (die, DW_AT_abstract_origin, cu);
- SET_FIELD_DWARF_BLOCK (call_site->target, NULL);
- if (!attr || (attr_form_is_block (attr) && DW_BLOCK (attr)->size == 0))
- /* Keep NULL DWARF_BLOCK. */;
- else if (attr_form_is_block (attr))
- {
- struct dwarf2_locexpr_baton *dlbaton;
-
- dlbaton = obstack_alloc (&objfile->objfile_obstack, sizeof
(*dlbaton));
- dlbaton->data = DW_BLOCK (attr)->data;
- dlbaton->size = DW_BLOCK (attr)->size;
- dlbaton->per_cu = cu->per_cu;
-
- SET_FIELD_DWARF_BLOCK (call_site->target, dlbaton);
- }
- else if (is_ref_attr (attr))
- {
- struct objfile *objfile = cu->objfile;
- struct dwarf2_cu *target_cu = cu;
- struct die_info *target_die;
-
- target_die = follow_die_ref_or_sig (die, attr, &target_cu);
- gdb_assert (target_cu->objfile == objfile);
- if (die_is_declaration (target_die, target_cu))
- {
- const char *target_physname;
-
- target_physname = dwarf2_physname (NULL, target_die, target_cu);
- if (target_physname == NULL)
- complaint (&symfile_complaints,
- _("DW_AT_GNU_call_site_target target DIE has invalid "
- "physname, for referencing DIE 0x%x [in module %s]"),
- die->offset, cu->objfile->name);
- else
- SET_FIELD_PHYSNAME (call_site->target, (char *) target_physname);
- }
- else
- {
- CORE_ADDR lowpc;
-
- /* DW_AT_entry_pc should be preferred. */
- if (!dwarf2_get_pc_bounds (target_die, &lowpc, NULL, target_cu, NULL))
- complaint (&symfile_complaints,
- _("DW_AT_GNU_call_site_target target DIE has invalid "
- "low pc, for referencing DIE 0x%x [in module %s]"),
- die->offset, cu->objfile->name);
- else
- SET_FIELD_PHYSADDR (call_site->target, lowpc + baseaddr);
- }
- }
- else
- complaint (&symfile_complaints,
- _("DW_TAG_GNU_call_site DW_AT_GNU_call_site_target is neither "
- "block nor reference, for DIE 0x%x [in module %s]"),
- die->offset, cu->objfile->name);
-
- call_site->per_cu = cu->per_cu;
-
- for (child_die = die->child;
- child_die && child_die->tag;
- child_die = sibling_die (child_die))
- {
- struct dwarf2_locexpr_baton *dlbaton;
- struct call_site_parameter *parameter;
-
- if (child_die->tag != DW_TAG_GNU_call_site_parameter)
- {
- /* Already printed the complaint above. */
- continue;
- }
-
- gdb_assert (call_site->parameter_count < nparams);
- parameter = &call_site->parameter[call_site->parameter_count];
-
- /* DW_AT_location specifies the register number. Value of the data
- assumed for the register is contained in DW_AT_GNU_call_site_value. */
-
- attr = dwarf2_attr (child_die, DW_AT_location, cu);
- if (!attr || !attr_form_is_block (attr))
- {
- complaint (&symfile_complaints,
- _("No DW_FORM_block* DW_AT_location for "
- "DW_TAG_GNU_call_site child DIE 0x%x [in module %s]"),
- child_die->offset, cu->objfile->name);
- continue;
- }
- parameter->dwarf_reg = dwarf_block_to_dwarf_reg (DW_BLOCK
(attr)->data,
- &DW_BLOCK (attr)->data[DW_BLOCK (attr)->size]);
- if (parameter->dwarf_reg == -1
- && !dwarf_block_to_sp_offset (gdbarch, DW_BLOCK (attr)->data,
- &DW_BLOCK (attr)->data[DW_BLOCK (attr)->size],
- &parameter->fb_offset))
- {
- complaint (&symfile_complaints,
- _("Only single DW_OP_reg or DW_OP_fbreg is supported "
- "for DW_FORM_block* DW_AT_location for "
- "DW_TAG_GNU_call_site child DIE 0x%x [in module %s]"),
- child_die->offset, cu->objfile->name);
- continue;
- }
-
- attr = dwarf2_attr (child_die, DW_AT_GNU_call_site_value, cu);
- if (!attr_form_is_block (attr))
- {
- complaint (&symfile_complaints,
- _("No DW_FORM_block* DW_AT_GNU_call_site_value for "
- "DW_TAG_GNU_call_site child DIE 0x%x [in module %s]"),
- child_die->offset, cu->objfile->name);
- continue;
- }
- parameter->value = DW_BLOCK (attr)->data;
- parameter->value_size = DW_BLOCK (attr)->size;
-
- /* Parameters are not pre-cleared by memset above. */
- parameter->data_value = NULL;
- parameter->data_value_size = 0;
- call_site->parameter_count++;
-
- attr = dwarf2_attr (child_die, DW_AT_GNU_call_site_data_value, cu);
- if (attr)
- {
- if (!attr_form_is_block (attr))
- complaint (&symfile_complaints,
- _("No DW_FORM_block* DW_AT_GNU_call_site_data_value for "
- "DW_TAG_GNU_call_site child DIE 0x%x [in module %s]"),
- child_die->offset, cu->objfile->name);
- else
- {
- parameter->data_value = DW_BLOCK (attr)->data;
- parameter->data_value_size = DW_BLOCK (attr)->size;
- }
- }
- }
-}
-
/* Get low and high pc attributes from DW_AT_ranges attribute value
OFFSET.
Return 1 if the attributes are present and valid, otherwise, return 0.
If RANGES_PST is not NULL we should setup
`objfile->psymtabs_addrmap'. */
@@ -6592,8 +6316,7 @@ dwarf2_get_pc_bounds (struct die_info *d
return 0;

*lowpc = low;
- if (highpc)
- *highpc = high;
+ *highpc = high;
return ret;
}

@@ -10078,10 +9801,9 @@ fixup_partial_die (struct partial_die_in
/* GCC might emit a nameless struct or union that has a linkage
name. See http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47510. */
if (part_die->name == NULL
- && (part_die->tag == DW_TAG_class_type
- || part_die->tag == DW_TAG_interface_type
- || part_die->tag == DW_TAG_structure_type
- || part_die->tag == DW_TAG_union_type)
+ && (part_die->tag == DW_TAG_structure_type
+ || part_die->tag == DW_TAG_union_type
+ || part_die->tag == DW_TAG_class_type)
&& part_die->linkage_name != NULL)
{
char *demangled;
@@ -10089,17 +9811,7 @@ fixup_partial_die (struct partial_die_in
demangled = cplus_demangle (part_die->linkage_name, DMGL_TYPES);
if (demangled)
{
- const char *base;
-
- /* Strip any leading namespaces/classes, keep only the base name.
- DW_AT_name for named DIEs does not contain the prefixes. */
- base = strrchr (demangled, ':');
- if (base && base > demangled && base[-1] == ':')
- base++;
- else
- base = demangled;
-
- part_die->name = obsavestring (base, strlen (base),
+ part_die->name = obsavestring (demangled, strlen (demangled),
&cu->objfile->objfile_obstack);
xfree (demangled);
}
@@ -12448,42 +12160,6 @@ guess_full_die_structure_name (struct di
return NULL;
}

-/* GCC might emit a nameless typedef that has a linkage name.
Determine the
- prefix part in such case. See
- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47510. */
-
-static char *
-anonymous_struct_prefix (struct die_info *die, struct dwarf2_cu *cu)
-{
- struct attribute *attr;
- char *base;
-
- if (die->tag != DW_TAG_class_type && die->tag != DW_TAG_interface_type
- && die->tag != DW_TAG_structure_type && die->tag !=
DW_TAG_union_type)
- return NULL;
-
- attr = dwarf2_attr (die, DW_AT_name, cu);
- if (attr != NULL && DW_STRING (attr) != NULL)
- return NULL;
-
- attr = dwarf2_attr (die, DW_AT_linkage_name, cu);
- if (attr == NULL)
- attr = dwarf2_attr (die, DW_AT_MIPS_linkage_name, cu);
- if (attr == NULL || DW_STRING (attr) == NULL)
- return NULL;
-
- /* dwarf2_name had to be already called. */
- gdb_assert (DW_STRING_IS_CANONICAL (attr));
-
- /* Strip the base name, keep any leading namespaces/classes. */
- base = strrchr (DW_STRING (attr), ':');
- if (base == NULL || base == DW_STRING (attr) || base[-1] != ':')
- return "";
-
- return obsavestring (DW_STRING (attr), &base[-1] - DW_STRING (attr),
- &cu->objfile->objfile_obstack);
-}
-
/* Return the name of the namespace/class that DIE is defined within,
or "" if we can't tell. The caller should not xfree the result.

@@ -12505,16 +12181,11 @@ determine_prefix (struct die_info *die,
struct die_info *parent, *spec_die;
struct dwarf2_cu *spec_cu;
struct type *parent_type;
- char *retval;

if (cu->language != language_cplus && cu->language != language_java
&& cu->language != language_fortran)
return "";

- retval = anonymous_struct_prefix (die, cu);
- if (retval)
- return retval;
-
/* We have to be careful in the presence of DW_AT_specification.
For example, with GCC 3.4, given the code

@@ -12806,21 +12477,12 @@ dwarf2_name (struct die_info *die, struc

if (demangled)
{
- char *base;
-
/* FIXME: we already did this for the partial symbol... */
- DW_STRING (attr) = obsavestring (demangled, strlen (demangled),
- &cu->objfile->objfile_obstack);
+ DW_STRING (attr)
+ = obsavestring (demangled, strlen (demangled),
+ &cu->objfile->objfile_obstack);
DW_STRING_IS_CANONICAL (attr) = 1;
xfree (demangled);
-
- /* Strip any leading namespaces/classes, keep only the base name.
- DW_AT_name for named DIEs does not contain the prefixes. */
- base = strrchr (DW_STRING (attr), ':');
- if (base && base > DW_STRING (attr) && base[-1] == ':')
- return &base[1];
- else
- return DW_STRING (attr);
}
}
break;
@@ -13004,8 +12666,6 @@ dwarf_tag_name (unsigned tag)
return "DW_TAG_PGI_kanji_type";
case DW_TAG_PGI_interface_block:
return "DW_TAG_PGI_interface_block";
- case DW_TAG_GNU_call_site:
- return "DW_TAG_GNU_call_site";
default:
return "DW_TAG_<unknown>";
}
@@ -14488,7 +14148,6 @@ decode_locdesc (struct dwarf_block *blk,

ctx->gdbarch = get_objfile_arch (objfile);
ctx->addr_size = cu->header.addr_size;
- ctx->ref_addr_size = dwarf2_per_cu_ref_addr_size (cu->per_cu);
ctx->offset = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT
(objfile));
ctx->baton = ctx;
ctx->funcs = &decode_locdesc_ctx_funcs;
@@ -15528,42 +15187,26 @@ dwarf2_per_cu_objfile (struct dwarf2_per
return objfile;
}

-/* Return comp_unit_head for PER_CU, either already available in PER_CU->CU
- (CU_HEADERP is unused in such case) or prepare a temporary copy at
- CU_HEADERP first. */
-
-static const struct comp_unit_head *
-per_cu_header_read_in (struct comp_unit_head *cu_headerp,
- struct dwarf2_per_cu_data *per_cu)
-{
- struct objfile *objfile;
- struct dwarf2_per_objfile *per_objfile;
- gdb_byte *info_ptr;
-
- if (per_cu->cu)
- return &per_cu->cu->header;
-
- objfile = per_cu->objfile;
- per_objfile = objfile_data (objfile, dwarf2_objfile_data_key);
- info_ptr = per_objfile->info.buffer + per_cu->offset;
-
- memset (cu_headerp, 0, sizeof (*cu_headerp));
- read_comp_unit_head (cu_headerp, info_ptr, objfile->obfd);
-
- return cu_headerp;
-}
-
/* Return the address size given in the compilation unit header for
CU. */

CORE_ADDR
dwarf2_per_cu_addr_size (struct dwarf2_per_cu_data *per_cu)
{
- struct comp_unit_head cu_header_local;
- const struct comp_unit_head *cu_headerp;
-
- cu_headerp = per_cu_header_read_in (&cu_header_local, per_cu);
-
- return cu_headerp->addr_size;
+ if (per_cu->cu)
+ return per_cu->cu->header.addr_size;
+ else
+ {
+ /* If the CU is not currently read in, we re-read its header. */
+ struct objfile *objfile = per_cu->objfile;
+ struct dwarf2_per_objfile *per_objfile
+ = objfile_data (objfile, dwarf2_objfile_data_key);
+ gdb_byte *info_ptr = per_objfile->info.buffer + per_cu->offset;
+ struct comp_unit_head cu_header;
+
+ memset (&cu_header, 0, sizeof cu_header);
+ read_comp_unit_head (&cu_header, info_ptr, objfile->obfd);
+ return cu_header.addr_size;
+ }
}

/* Return the offset size given in the compilation unit header for CU. */
@@ -15571,28 +15214,21 @@ dwarf2_per_cu_addr_size (struct dwarf2_p
int
dwarf2_per_cu_offset_size (struct dwarf2_per_cu_data *per_cu)
{
- struct comp_unit_head cu_header_local;
- const struct comp_unit_head *cu_headerp;
-
- cu_headerp = per_cu_header_read_in (&cu_header_local, per_cu);
-
- return cu_headerp->offset_size;
-}
-
-/* See its dwarf2loc.h declaration. */
-
-int
-dwarf2_per_cu_ref_addr_size (struct dwarf2_per_cu_data *per_cu)
-{
- struct comp_unit_head cu_header_local;
- const struct comp_unit_head *cu_headerp;
-
- cu_headerp = per_cu_header_read_in (&cu_header_local, per_cu);
-
- if (cu_headerp->version == 2)
- return cu_headerp->addr_size;
+ if (per_cu->cu)
+ return per_cu->cu->header.offset_size;
else
- return cu_headerp->offset_size;
+ {
+ /* If the CU is not currently read in, we re-read its header. */
+ struct objfile *objfile = per_cu->objfile;
+ struct dwarf2_per_objfile *per_objfile
+ = objfile_data (objfile, dwarf2_objfile_data_key);
+ gdb_byte *info_ptr = per_objfile->info.buffer + per_cu->offset;
+ struct comp_unit_head cu_header;
+
+ memset (&cu_header, 0, sizeof cu_header);
+ read_comp_unit_head (&cu_header, info_ptr, objfile->obfd);
+ return cu_header.offset_size;
+ }
}

/* Return the text offset of the CU. The returned offset comes from
@@ -16691,6 +16327,14 @@ write_one_signatured_type (void **slot,
return 1;
}

+/* A cleanup function for an htab_t. */
+
+static void
+cleanup_htab (void *arg)
+{
+ htab_delete (arg);
+}
+
/* Create an index file for OBJFILE in the directory DIR. */

static void
@@ -16747,7 +16391,7 @@ write_psymtabs_to_index (struct objfile

psyms_seen = htab_create_alloc (100, htab_hash_pointer, htab_eq_pointer,
NULL, xcalloc, xfree);
- make_cleanup_htab_delete (psyms_seen);
+ make_cleanup (cleanup_htab, psyms_seen);

/* While we're scanning CU's create a table that maps a psymtab pointer
(which is what addrmap records) to its index (which is what is
recorded
@@ -16757,7 +16401,7 @@ write_psymtabs_to_index (struct objfile
hash_psymtab_cu_index,
eq_psymtab_cu_index,
NULL, xcalloc, xfree);
- make_cleanup_htab_delete (cu_index_htab);
+ make_cleanup (cleanup_htab, cu_index_htab);
psymtab_cu_index_map = (struct psymtab_cu_index_map *)
xmalloc (sizeof (struct psymtab_cu_index_map)
* dwarf2_per_objfile->n_comp_units);