Re: [PATCH,V2 5/5] CTF: multi-CU and archive support

[Wei-min Pan <weimin.pan@oracle.com>]

On 3/2/2021 3:15 PM, Lancelot SIX wrote:
> Hi,
>
> I have few comments spread above.
>
> I hope this help.
>
> Le Mon, Mar 01, 2021 at 08:53:38PM -0500, Weimin Pan via Gdb-patches a écrit :
>> Now gdb is capable of debugging executable, which consists of multiple
>> compilation units, with CTF. An executable could potentially have one
>> or more archives, which, in CTF context, contain conflicting types.
>> When comparing to DWARF2, there is a major difference in the type sections,
>>
>> all changes were made in ctfread.c where elfctf_build_psymtabs and
>> scan_partial_symbols, with the new ctf_per_tu_data struct, were modify to
>> handle archives which were treated as dependencies in gdb, via the ctf
>> archive iterator and its callback build_ctf_archive_member, and were then
>> expanded with expand_dependencies when psymtabs were expanded.
>>
>> Also changes were made to handle CTF's data object section and function
>> info section which now share the same format for their contents - an array
>> of type IDs. New functions ctf_psymtab_add_stt_entries, which is called by
>> ctf_psymtab_add_stt_obj and ctf_psymtab_add_stt_func, and add_stt_entries,
>> which is called by add_stt_obj and add_stt_func when setting up psymtabs
>> and full symtab, respectively.
>>
>> ---
>>   gdb/ChangeLog                             |  15 ++
>>   gdb/ctfread.c                             | 365 +++++++++++++++++++-----------
>>   gdb/testsuite/ChangeLog                   |   5 +
>>   gdb/testsuite/gdb.ctf/cross-tu-cyclic-1.c |  18 ++
>>   gdb/testsuite/gdb.ctf/cross-tu-cyclic-2.c |  16 ++
>>   gdb/testsuite/gdb.ctf/cross-tu-cyclic-3.c |   3 +
>>   gdb/testsuite/gdb.ctf/cross-tu-cyclic-4.c |   4 +
>>   gdb/testsuite/gdb.ctf/cross-tu-cyclic.exp |  43 ++++
>>   gdb/testsuite/gdb.ctf/ctf-a.c             |  32 +++
>>   gdb/testsuite/gdb.ctf/ctf-a.h             |  22 ++
>>   gdb/testsuite/gdb.ctf/ctf-b.c             |  25 ++
>>   gdb/testsuite/gdb.ctf/ctf-b.h             |  22 ++
>>   gdb/testsuite/gdb.ctf/ctf-c.c             |  25 ++
>>   gdb/testsuite/gdb.ctf/ctf-c.h             |  21 ++
>>   gdb/testsuite/gdb.ctf/multi.exp           |  42 ++++
>>   15 files changed, 526 insertions(+), 132 deletions(-)
>>   create mode 100644 gdb/testsuite/gdb.ctf/cross-tu-cyclic-1.c
>>   create mode 100644 gdb/testsuite/gdb.ctf/cross-tu-cyclic-2.c
>>   create mode 100644 gdb/testsuite/gdb.ctf/cross-tu-cyclic-3.c
>>   create mode 100644 gdb/testsuite/gdb.ctf/cross-tu-cyclic-4.c
>>   create mode 100644 gdb/testsuite/gdb.ctf/cross-tu-cyclic.exp
>>   create mode 100644 gdb/testsuite/gdb.ctf/ctf-a.c
>>   create mode 100644 gdb/testsuite/gdb.ctf/ctf-a.h
>>   create mode 100644 gdb/testsuite/gdb.ctf/ctf-b.c
>>   create mode 100644 gdb/testsuite/gdb.ctf/ctf-b.h
>>   create mode 100644 gdb/testsuite/gdb.ctf/ctf-c.c
>>   create mode 100644 gdb/testsuite/gdb.ctf/ctf-c.h
>>   create mode 100644 gdb/testsuite/gdb.ctf/multi.exp
>>
>> diff --git a/gdb/ChangeLog b/gdb/ChangeLog
>> index 31cac5c..52a325f 100644
>> --- a/gdb/ChangeLog
>> +++ b/gdb/ChangeLog
>> @@ -1,5 +1,20 @@
>>   2021-02-26  Weimin Pan  <weimin.pan@oracle.com>
>>   
>> +	* ctfread.c (ctf_per_tu_data): New struct.
>> +	(add_stt_entries): New funtion.
>> +	(add_stt_obj): Use it.
>> +	(add_stt_func): Likewise.
>> +	(ctf_psymtab_add_stt_entries): New function.
>> +	(ctf_psymtab_add_stt_obj): Use it.
>> +	(ctf_psymtab_add_stt_func): Likewise.
>> +	(ctf_psymtab::expand_psymtab): Call expand_dependencies to expand
>> +	archives.
>> +	(scan_partial_symbols): Set up partial symtab list.
>> +	(build_ctf_archive_member): New function.
>> +	(elfctf_build_psymtabs): Call Iterater to set up archives.
>> +
>> +2021-02-26  Weimin Pan  <weimin.pan@oracle.com>
>> +
>>   	* ctfread.c (ctf_psymtab_add_enums): New function.
>>   	(ctf_psymtab_type_cb): call ctf_psymtab_add_enums.
>>   
>> diff --git a/gdb/ctfread.c b/gdb/ctfread.c
>> index bb73949..9ddd1db 100644
>> --- a/gdb/ctfread.c
>> +++ b/gdb/ctfread.c
>> @@ -80,6 +80,7 @@
>>   #include "complaints.h"
>>   #include "block.h"
>>   #include "ctfread.h"
>> +#include "objfiles.h"
>>   #include "psympriv.h"
>>   
>>   #if ENABLE_LIBCTF
>> @@ -116,6 +117,7 @@ struct ctf_context
>>     ctf_dict_t *fp;
>>     struct objfile *of;
>>     partial_symtab *pst;
>> +  ctf_archive_t *arc;
>>     struct buildsym_compunit *builder;
>>   };
>>   
>> @@ -162,6 +164,40 @@ struct ctf_field_info
>>     std::vector<struct decl_field> nested_types_list;
>>   };
>>   
>> +/* Persistent data held for a translation unit.  */
>> +
>> +struct ctf_per_tu_data
>> +{
>> +  ctf_dict_t *fp;
>> +  struct objfile *of;
>> +  ctf_archive_t *arc;
>> +  ctf_psymtab *parent_psymtab;
>> +  // struct partial_symtab *psymtab;
> I guess this was left here from a previous development iteration and
> should be removed.

Yes, it will be removed.

>> +  /* Push P to the back of IMPORTED_SYMTABS, allocated IMPORTED_SYMTABS
>> +     first if required.  */
>> +  void imported_symtabs_push (struct partial_symtab *p)
>> +  {
>> +    if (imported_symtabs == nullptr)
>> +      imported_symtabs = new std::vector <struct partial_symtab *>;
>> +    imported_symtabs->push_back (p);
>> +  }
>> +  /* Return the size of IMPORTED_SYMTABS if it is allocated, otherwise
>> +     return 0.  */
>> +  size_t imported_symtabs_size () const
>> +  {
>> +    if (imported_symtabs == nullptr)
>> +      return 0;
>> +    return imported_symtabs->size ();
>> +  }
>> +
>> +  /* Delete IMPORTED_SYMTABS and set the pointer back to nullptr.  */
>> +  void imported_symtabs_free ()
>> +  {
>> +    delete imported_symtabs;
>> +    imported_symtabs = nullptr;
>> +  }
>> +  std::vector <struct partial_symtab *> *imported_symtabs;
>> +};
>  From the usage of this struct, it looks like imported_symtaps can be a
> std::vector (not pointer to std::vector). This would remove the need of
> imported_sympabs_push, imported_smtabs_size and imported symtabs_free
> altogether.
>
> The all struct becomes
>
> struct ctf_per_tu_data
> {
>    ctf_dict_t *fp;
>    struct objfile *of;
>    ctf_archive_t *arc;
>    ctf_psymtab *parent_psymtab;
>    std::vector<struct partial_symtab *> imported_symtabs;
> }
>
> Then x.imported_symtabs_push (p) becomes
> x.imported_symtabs.push_back (p), x.imported_symtabs_size () becomes
> x.imported_symtabs.size () and imported_symtabs_free becomes
> unnecessary.

This indeed simplifies the struct and saves a call. Nice, will do.

>>   /* Local function prototypes */
>>   
>> @@ -241,10 +277,8 @@ struct ctf_tid_and_type
>>     ids.tid = tid;
>>     ids.type = typ;
>>     slot = (struct ctf_tid_and_type **) htab_find_slot (htab, &ids, INSERT);
>> -  if (*slot)
>> -    complaint (_("An internal GDB problem: ctf_ id_t %ld type already set"),
>> -	       (tid));
>> -  *slot = XOBNEW (&of->objfile_obstack, struct ctf_tid_and_type);
>> +  if (*slot == 0)
>> +    *slot = XOBNEW (&of->objfile_obstack, struct ctf_tid_and_type);
>>     **slot = ids;
>>     return typ;
>>   }
>> @@ -459,7 +493,7 @@ struct ctf_tid_and_type
>>     struct symbol *sym = NULL;
>>   
>>     gdb::unique_xmalloc_ptr<char> name (ctf_type_aname_raw (fp, tid));
>> -  if (name != NULL)
>> +  if (name != NULL && strcmp(name.get (), ""))
> You missed a space after strcmp and a explicit comparison of the
> returned value.
>
> if (name != nullptr && strcmp (name.get (), "") != 0)

OK, will fix it.

>>       {
>>         sym = new (&objfile->objfile_obstack) symbol;
>>         OBJSTAT (objfile, n_syms++);
>> @@ -943,7 +977,7 @@ struct ctf_tid_and_type
>>         if (target_type == NULL)
>>   	{
>>   	  complaint (_("read_pointer_type: NULL target type (%ld)"), btid);
>> -	  target_type = objfile_type (ccp->of)->builtin_error;
>> +	  target_type = objfile_type (of)->builtin_error;
>>   	}
>>       }
>>   
>> @@ -1055,6 +1089,12 @@ struct ctf_tid_and_type
>>     struct type *type;
>>     uint32_t kind;
>>   
>> +  if (info_verbose)
>> +    {
>> +      printf_filtered (_("ctf_add_type_cb adding tid %lx..."), tid);
>> +      gdb_flush (gdb_stdout);
>> +    }
>> +
>>     /* Check if tid's type has already been defined.  */
>>     type = get_tid_type (ccp->of, tid);
>>     if (type != NULL)
>> @@ -1141,7 +1181,8 @@ struct ctf_tid_and_type
>>   	if (type)
>>   	  {
>>   	    sym = new_symbol (ccp, type, id);
>> -	    sym->compute_and_set_names (name, false, ccp->of->per_bfd);
>> +	    if (sym)
> Here also, if (sym != nullptr).

OK, will fix it.

>> +	      sym->compute_and_set_names (name, false, ccp->of->per_bfd);
>>   	  }
>>   	break;
>>         case CTF_K_STRUCT:
>> @@ -1171,81 +1212,48 @@ struct ctf_tid_and_type
>>     return 0;
>>   }
>>   
>> -/* Add an ELF STT_OBJ symbol with index IDX to the symbol table.  */
>> +/* Add entries in either data objects or function info section, controlled
>> +   by FUNCTIONS.  */
>>   
>> -static struct symbol *
>> -add_stt_obj (struct ctf_context *ccp, unsigned long idx)
>> +static void
>> +add_stt_entries (struct ctf_context *ccp, int functions)
>>   {
>> -  struct symbol *sym;
>> -  struct type *type;
>> +  ctf_next_t *i = NULL;
>> +  const char *tname;
>>     ctf_id_t tid;
>> +  struct symbol *sym = NULL;
>> +  struct type *type;
>>   
>> -  if ((tid = ctf_lookup_by_symbol (ccp->fp, idx)) == CTF_ERR)
>> -    return NULL;
>> -
>> -  type = fetch_tid_type (ccp, tid);
>> -  if (type == NULL)
>> -    return NULL;
>> -
>> -  sym = new_symbol (ccp, type, tid);
>> -
>> -  return sym;
>> +  while ((tid = ctf_symbol_next (ccp->fp, &i, &tname, functions)) != CTF_ERR)
>> +    {
>> +      type = get_tid_type (ccp->of, tid);
>> +      if (type == NULL)
>> +	continue;
>> +      sym = new (&ccp->of->objfile_obstack) symbol;
>> +      OBJSTAT (ccp->of, n_syms++);
>> +      SYMBOL_TYPE (sym) = type;
>> +      SYMBOL_DOMAIN (sym) = VAR_DOMAIN;
>> +      SYMBOL_ACLASS_INDEX (sym) = LOC_STATIC;
>> +      sym->compute_and_set_names (tname, false, ccp->of->per_bfd);
>> +      add_symbol_to_list (sym, ccp->builder->get_global_symbols ());
>> +      set_symbol_address (ccp->of, sym, tname);
>> +    }
>>   }
>>   
>> -/* Add an ELF STT_FUNC symbol with index IDX to the symbol table.  */
>> +/* Add entries in data objects section.  */
>>   
>> -static struct symbol *
>> -add_stt_func (struct ctf_context *ccp, unsigned long idx)
>> +static void
>> +add_stt_obj (struct ctf_context *ccp)
>>   {
>> -  struct type *ftype, *atyp, *rettyp;
>> -  struct symbol *sym;
>> -  ctf_funcinfo_t finfo;
>> -  ctf_id_t argv[32];
>> -  uint32_t argc;
>> -  ctf_id_t tid;
>> -  struct type *void_type = objfile_type (ccp->of)->builtin_void;
>> -
>> -  if (ctf_func_info (ccp->fp, idx, &finfo) == CTF_ERR)
>> -    return NULL;
>> -
>> -  argc = finfo.ctc_argc;
>> -  if (ctf_func_args (ccp->fp, idx, argc, argv) == CTF_ERR)
>> -    return NULL;
>> -
>> -  gdb::unique_xmalloc_ptr<char> name (ctf_type_aname_raw (ccp->fp, idx));
>> -  if (name == NULL)
>> -    return NULL;
>> -
>> -  tid = ctf_lookup_by_symbol (ccp->fp, idx);
>> -  ftype = fetch_tid_type (ccp, tid);
>> -  if (finfo.ctc_flags & CTF_FUNC_VARARG)
>> -    ftype->set_has_varargs (true);
>> -  ftype->set_num_fields (argc);
>> -
>> -  /* If argc is 0, it has a "void" type.  */
>> -  if (argc != 0)
>> -    ftype->set_fields
>> -      ((struct field *) TYPE_ZALLOC (ftype, argc * sizeof (struct field)));
>> +  add_stt_entries (ccp, 0);
>> +}
>>   
>> -  /* TYPE_FIELD_TYPE must never be NULL.  Fill it with void_type, if failed
>> -     to find the argument type.  */
>> -  for (int iparam = 0; iparam < argc; iparam++)
>> -    {
>> -      atyp = fetch_tid_type (ccp, argv[iparam]);
>> -      if (atyp)
>> -	ftype->field (iparam).set_type (atyp);
>> -      else
>> -	ftype->field (iparam).set_type (void_type);
>> -    }
>> +/* Add entries in function info section.  */
>>   
>> -  sym = new_symbol (ccp, ftype, tid);
>> -  rettyp = fetch_tid_type (ccp, finfo.ctc_return);
>> -  if (rettyp != NULL)
>> -    SYMBOL_TYPE (sym) = rettyp;
>> -  else
>> -    SYMBOL_TYPE (sym) = void_type;
>> -
>> -  return sym;
>> +static void
>> +add_stt_func (struct ctf_context *ccp)
>> +{
>> +  add_stt_entries (ccp, 1);
>>   }
>>   
>>   /* Get text segment base for OBJFILE, TSIZE contains the segment size.  */
>> @@ -1268,12 +1276,20 @@ struct ctf_tid_and_type
>>   		  struct objfile *of, CORE_ADDR text_offset)
>>   {
>>     struct ctf_context *ccp;
>> +  ctf_psymtab *dp;
>>   
>>     ccp = pst->context;
>>     ccp->builder = new buildsym_compunit
>>   		       (of, of->original_name, NULL,
>>   		       language_c, text_offset);
>>     ccp->builder->record_debugformat ("ctf");
>> +
>> +  for (int i = 0; i < pst->number_of_dependencies; i++)
>> +    {
>> +      dp = (ctf_psymtab *)pst->dependencies[i];
>> +      dp->context->builder = ccp->builder;
>> +      dp->context->of = of;
>> +    }
>>   }
>>   
>>   /* Finish reading symbol/type definitions in CTF format.
>> @@ -1315,46 +1331,94 @@ struct ctf_tid_and_type
>>   	       ctf_errmsg (ctf_errno (ccp->fp)));
>>   }
>>   
>> +/* Add entries in either data objects or function info section, controlled
>> +   by FUNCTIONS, to psymtab.  */
>> +
>> +static void
>> +ctf_psymtab_add_stt_entries (ctf_dict_t *cfp, ctf_psymtab *pst,
>> +			     struct objfile *of, int functions)
>> +{
>> +  ctf_next_t *i = NULL;
>> +  ctf_id_t tid;
>> +  const char *tname;
>> +
>> +  while ((tid = ctf_symbol_next (cfp, &i, &tname, functions)) != CTF_ERR)
>> +    {
>> +      uint32_t kind = ctf_type_kind (cfp, tid);
>> +      address_class aclass;
>> +      domain_enum tdomain;
>> +      switch (kind)
>> +	{
>> +	  case CTF_K_STRUCT:
>> +	  case CTF_K_UNION:
>> +	  case CTF_K_ENUM:
>> +	    tdomain = STRUCT_DOMAIN;
>> +	    break;
>> +	  default:
>> +	    tdomain = VAR_DOMAIN;
>> +	    break;
>> +	}
>> +
>> +      if (kind == CTF_K_FUNCTION)
>> +	aclass = LOC_STATIC;
>> +      else if (kind == CTF_K_CONST)
>> +	aclass = LOC_CONST;
>> +      else
>> +	aclass = LOC_TYPEDEF;
>> +
>> +      pst->add_psymbol (tname, true,
>> +			tdomain, aclass, -1,
>> +			psymbol_placement::GLOBAL,
>> +			0, language_c, of);
>> +    }
>> +}
>> +
>> +/* Add entries in data objects section to psymtab.  */
>> +
>> +static void
>> +ctf_psymtab_add_stt_obj (ctf_dict_t *cfp, ctf_psymtab *pst,
>> +			 struct objfile *of)
>> +{
>> +  ctf_psymtab_add_stt_entries (cfp, pst, of, 0);
>> +}
>> +
>> +/* Add entries in function info section to psymtab.  */
>> +
>> +static void
>> +ctf_psymtab_add_stt_func (ctf_dict_t *cfp, ctf_psymtab *pst,
>> +			  struct objfile *of)
>> +{
>> +  ctf_psymtab_add_stt_entries (cfp, pst, of, 1);
>> +}
>> +
>>   /* Read in full symbols for PST, and anything it depends on.  */
>>   
>>   void
>>   ctf_psymtab::expand_psymtab (struct objfile *objfile)
>>   {
>> -  struct symbol *sym;
>>     struct ctf_context *ccp;
>>   
>>     gdb_assert (!readin);
>>   
>>     ccp = context;
>> +  expand_dependencies (objfile);
>>   
>>     /* Iterate over entries in data types section.  */
>>     if (ctf_type_iter (ccp->fp, ctf_add_type_cb, ccp) == CTF_ERR)
>> -    complaint (_("ctf_type_iter psymtab_to_symtab failed - %s"),
>> +    complaint (_("ctf_type_iter expand_psymtab failed - %s"),
>>   	       ctf_errmsg (ctf_errno (ccp->fp)));
>>   
>>   
>>     /* Iterate over entries in variable info section.  */
>>     if (ctf_variable_iter (ccp->fp, ctf_add_var_cb, ccp) == CTF_ERR)
>> -    complaint (_("ctf_variable_iter psymtab_to_symtab failed - %s"),
>> +    complaint (_("ctf_variable_iter expand_psymtab failed - %s"),
>>   	       ctf_errmsg (ctf_errno (ccp->fp)));
>>   
>>     /* Add entries in data objects and function info sections.  */
>> -  for (unsigned long i = 0; ; i++)
>> -    {
>> -      sym = add_stt_obj (ccp, i);
>> -      if (sym == NULL)
>> -	{
>> -	  if (ctf_errno (ccp->fp) == EINVAL
>> -	      || ctf_errno (ccp->fp) == ECTF_NOSYMTAB)
>> -	    break;
>> -	  sym = add_stt_func (ccp, i);
>> -	}
>> -      if (sym == NULL)
>> -	continue;
>> -
>> -      set_symbol_address (ccp->of, sym, sym->linkage_name ());
>> -    }
>> +  add_stt_obj (ccp);
>> +  add_stt_func (ccp);
>>   
>> +  ctf_dict_close (ccp->fp);
>>     readin = true;
>>   }
>>   
>> @@ -1407,6 +1471,7 @@ struct ctf_tid_and_type
>>   
>>   static ctf_psymtab *
>>   create_partial_symtab (const char *name,
>> +		       ctf_archive_t *arc,
>>   		       ctf_dict_t *cfp,
>>   		       struct objfile *objfile)
>>   {
>> @@ -1416,10 +1481,11 @@ struct ctf_tid_and_type
>>     pst = new ctf_psymtab (name, objfile, 0);
>>   
>>     ccx = XOBNEW (&objfile->objfile_obstack, struct ctf_context);
>> +  ccx->arc = arc;
>>     ccx->fp = cfp;
>> +  ctf_ref (cfp);
>>     ccx->of = objfile;
>>     ccx->pst = pst;
>> -  ccx->builder = nullptr;
>>     pst->context = ccx;
>>   
>>     return pst;
>> @@ -1506,12 +1572,29 @@ struct ctf_tid_and_type
>>      debugging information is available.  */
>>   
>>   static void
>> -scan_partial_symbols (ctf_dict_t *cfp, struct objfile *of)
>> +scan_partial_symbols (ctf_dict_t *cfp,
>> +		      struct ctf_per_tu_data *pcu,
>> +		      const char *aname)
>>   {
>> -  bfd *abfd = of->obfd;
>> -  const char *name = bfd_get_filename (abfd);
>> -  ctf_psymtab *pst = create_partial_symtab (name, cfp, of);
>> +  struct objfile *of = pcu->of;
>> +  bool isparent = 0;
>> +
>> +  if (info_verbose)
>> +    {
>> +      printf_filtered (_("Scanning partial symbols for %s..."), aname);
>> +      gdb_flush (gdb_stdout);
>> +    }
>> +
>> +  if (strcmp (aname, ".ctf") == 0)
>> +    isparent = 1;
>>   
>> +  if (info_verbose)
>> +    {
>> +      printf_filtered (_("Creating partial symtab %s..."), aname);
>> +      gdb_flush (gdb_stdout);
>> +    }
>> +
>> +  ctf_psymtab *pst = create_partial_symtab (aname, pcu->arc, cfp, of);
>>     struct ctf_context *ccx = pst->context;
>>   
>>     if (ctf_type_iter (cfp, ctf_psymtab_type_cb, ccx) == CTF_ERR)
>> @@ -1525,46 +1608,39 @@ struct ctf_tid_and_type
>>     /* Scan CTF object and function sections which correspond to each
>>        STT_FUNC or STT_OBJECT entry in the symbol table,
>>        pick up what init_symtab has done.  */
>> -  for (unsigned long idx = 0; ; idx++)
>> -    {
>> -      ctf_id_t tid;
>> -      if ((tid = ctf_lookup_by_symbol (cfp, idx)) == CTF_ERR)
>> -	{
>> -	if (ctf_errno (cfp) == EINVAL || ctf_errno (cfp) == ECTF_NOSYMTAB)
>> -	  break;	// Done, reach end of the section.
>> -	else
>> -	  continue;
>> -	}
>> -      gdb::unique_xmalloc_ptr<char> tname (ctf_type_aname_raw (cfp, tid));
>> -      uint32_t kind = ctf_type_kind (cfp, tid);
>> -      address_class aclass;
>> -      domain_enum tdomain;
>> -      switch (kind)
>> -	{
>> -	  case CTF_K_STRUCT:
>> -	  case CTF_K_UNION:
>> -	  case CTF_K_ENUM:
>> -	    tdomain = STRUCT_DOMAIN;
>> -	    break;
>> -	  default:
>> -	    tdomain = VAR_DOMAIN;
>> -	    break;
>> -	}
>> +  ctf_psymtab_add_stt_obj (cfp, pst, of);
>> +  ctf_psymtab_add_stt_func (cfp, pst, of);
>>   
>> -      if (kind == CTF_K_FUNCTION)
>> -	aclass = LOC_STATIC;
>> -      else if (kind == CTF_K_CONST)
>> -	aclass = LOC_CONST;
>> -      else
>> -	aclass = LOC_TYPEDEF;
>> +  pst->end ();
>>   
>> -      pst->add_psymbol (tname.get (), true,
>> -			tdomain, aclass, -1,
>> -			psymbol_placement::STATIC,
>> -			0, language_c, of);
>> +  if (isparent)
>> +    pcu->parent_psymtab = pst;
>> +  else
>> +    pcu->imported_symtabs_push (pst);
>> +}
>> +
>> +/* Callback to build the psymtab for archive member NAME.  */
>> +
>> +static int
>> +build_ctf_archive_member (ctf_dict_t *ctf, const char *name, void *arg)
> I do not see the advantage of having arg passed as a void *.  It is
> casted unconditionally to a struct ctf_per_tu_data * and dereferenced
> just after that.
>
> Why not just pass the argument as a struct ctf_per_tu_data * directly?

build_ctf_archive_member is the callback function of ctf_archive_iter 
and is of
type ctf_member_f which is defined in ctf-api.h:

typedef int ctf_member_f (const char *name, ctf_id_t membtype,
                           unsigned long offset, void *arg);

and the last argument "pcu" of type struct ctf_per_tu_data * is being 
passed in call:

         if (ctf_archive_iter (arc, build_ctf_archive_member, &pcu) < 0)

The conversion is necessary.

>> +{
>> +  struct ctf_per_tu_data *tup = (struct ctf_per_tu_data *) arg;
>> +  ctf_dict_t *parent = tup->fp;
>> +
>> +  if (strcmp (name, ".ctf") != 0)
>> +    {
>> +      ctf_import (ctf, parent);
>>       }
>>   
>> -  pst->end ();
>> +  if (info_verbose)
>> +    {
>> +      printf_filtered (_("Scanning archive member %s..."), name);
>> +      gdb_flush (gdb_stdout);
>> +    }
>> +
>> +  scan_partial_symbols (ctf, tup, name);
>> +
>> +  return 0;
>>   }
>>   
>>   /* Read CTF debugging information from a BFD section.  This is
>> @@ -1574,6 +1650,7 @@ struct ctf_tid_and_type
>>   void
>>   elfctf_build_psymtabs (struct objfile *of)
>>   {
>> +  struct ctf_per_tu_data pcu;
>>     bfd *abfd = of->obfd;
>>     int err;
>>   
>> @@ -1588,7 +1665,31 @@ struct ctf_tid_and_type
>>   	   bfd_get_filename (abfd), ctf_errmsg (err));
>>     ctf_dict_key.emplace (of, fp);
>>   
>> -  scan_partial_symbols (fp, of);
>> +  pcu.fp = fp;
>> +  pcu.of = of;
>> +  pcu.arc = arc;
>> +  pcu.imported_symtabs = nullptr;
>> +
>> +  if (ctf_archive_iter (arc, build_ctf_archive_member, &pcu) < 0)
>> +    error (_("ctf_archive_iter failed in input file %s: - %s"),
>> +	   bfd_get_filename (abfd), ctf_errmsg (err));
>> +
>> +  int arch_cnt = pcu.imported_symtabs_size ();
> I guess it could be declared const.

Will do.

>> +  struct partial_symtab *parent_pst = pcu.parent_psymtab;
>> +
>> +  if (parent_pst && arch_cnt)
> if (parent_pst != nullptr && arch_cnt != 0)

OK, will fix it.

>> +    {
>> +      /* Fill in the 'dependencies'.  */
>> +      parent_pst->number_of_dependencies = arch_cnt;
>> +      parent_pst->dependencies
>> +	= of->partial_symtabs->allocate_dependencies (arch_cnt);
>> +      for (int i = 0; i < arch_cnt; ++i)
>> +	{
>> +	  parent_pst->dependencies[i]
>> +	    = pcu.imported_symtabs->at (i);
>> +	}
>> +      pcu.imported_symtabs_free ();
>> +    }
>>   }
>>   
>>   #else
>> diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
>> index 4f9a3ec..3501669 100644
>> --- a/gdb/testsuite/ChangeLog
>> +++ b/gdb/testsuite/ChangeLog
>> @@ -1,5 +1,10 @@
>>   2021-02-26  Weimin Pan  <weimin.pan@oracle.com>
>>   
>> +	* gdb.ctf/cross-tu-cyclic.exp: New file.
>> +	* gdb.ctf/multi.exp: New file.
>> +
>> +2021-02-26  Weimin Pan  <weimin.pan@oracle.com>
>> +
>>   	* gdb.base/ctf-ptype.c: Add struct link containing a forward
>>   	reference type.
>>   	* gdb.base/ctf-ptype.exp: Add "ptype struct link"
>> diff --git a/gdb/testsuite/gdb.ctf/cross-tu-cyclic-1.c b/gdb/testsuite/gdb.ctf/cross-tu-cyclic-1.c
>> new file mode 100644
>> index 0000000..fe52b9e
>> --- /dev/null
>> +++ b/gdb/testsuite/gdb.ctf/cross-tu-cyclic-1.c
>> @@ -0,0 +1,18 @@
>> +struct A;
>> +struct B
>> +{
>> +  int foo;
>> +  struct A *bar;
>> +};
>> +
>> +struct A
>> +{
>> +  long a;
>> +  struct B *foo;
>> +};
>> +
>> +static struct A *foo __attribute__((used));
>> +
>> +int main()
>> +{
>> +}
>> diff --git a/gdb/testsuite/gdb.ctf/cross-tu-cyclic-2.c b/gdb/testsuite/gdb.ctf/cross-tu-cyclic-2.c
>> new file mode 100644
>> index 0000000..aa2d177
>> --- /dev/null
>> +++ b/gdb/testsuite/gdb.ctf/cross-tu-cyclic-2.c
>> @@ -0,0 +1,16 @@
>> +struct B;
>> +struct A
>> +{
>> +  long a;
>> +  struct B *foo;
>> +  struct C *bar;
>> +};
>> +
>> +struct C
>> +{
>> +  struct B *foo;
>> +  int b;
>> +};
>> +
>> +static struct C *foo __attribute__((used));
>> +static struct A *bar __attribute__((used));
>> diff --git a/gdb/testsuite/gdb.ctf/cross-tu-cyclic-3.c b/gdb/testsuite/gdb.ctf/cross-tu-cyclic-3.c
>> new file mode 100644
>> index 0000000..19947e8
>> --- /dev/null
>> +++ b/gdb/testsuite/gdb.ctf/cross-tu-cyclic-3.c
>> @@ -0,0 +1,3 @@
>> +struct A { struct B *foo; };
>> +static struct A *a __attribute__((__used__));
>> +static struct A *conflicty __attribute__((__used__));
>> diff --git a/gdb/testsuite/gdb.ctf/cross-tu-cyclic-4.c b/gdb/testsuite/gdb.ctf/cross-tu-cyclic-4.c
>> new file mode 100644
>> index 0000000..6e0c957
>> --- /dev/null
>> +++ b/gdb/testsuite/gdb.ctf/cross-tu-cyclic-4.c
>> @@ -0,0 +1,4 @@
>> +struct A { struct B *foo; };
>> +struct B { struct B *next; };
>> +static struct A *a __attribute__((__used__));
>> +static struct B *conflicty __attribute__((__used__));
>> diff --git a/gdb/testsuite/gdb.ctf/cross-tu-cyclic.exp b/gdb/testsuite/gdb.ctf/cross-tu-cyclic.exp
>> new file mode 100644
>> index 0000000..2c5ad8d
>> --- /dev/null
>> +++ b/gdb/testsuite/gdb.ctf/cross-tu-cyclic.exp
>> @@ -0,0 +1,43 @@
>> +# Copyright 2021 Free Software Foundation, Inc.
>> +
>> +# This program is free software; you can redistribute it and/or modify
>> +# it under the terms of the GNU General Public License as published by
>> +# the Free Software Foundation; either version 3 of the License, or
>> +# (at your option) any later version.
>> +#
>> +# This program is distributed in the hope that it will be useful,
>> +# but WITHOUT ANY WARRANTY; without even the implied warranty of
>> +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>> +# GNU General Public License for more details.
>> +#
>> +# You should have received a copy of the GNU General Public License
>> +# along with this program.  If not, see <https://urldefense.com/v3/__http://www.gnu.org/licenses/__;!!GqivPVa7Brio!MlnQ4nwBBbhjsCOlrkvxnKDpvrQ5BtDctjA14y8Sh72MPt3sVujLIe8lqYzl-as2$ >.
>> +
>> +# This file is a subset of ptype.exp written by Rob Savoye. (rob@cygnus.com)
>> +
>> +if [skip_ctf_tests] {
>> +    unsupported "no CTF debug format support, or CTF disabled in GDB"
>> +    return 0
>> +}
>> +
>> +standard_testfile cross-tu-cyclic-1.c  cross-tu-cyclic-2.c \
>> +	cross-tu-cyclic-3.c  cross-tu-cyclic-4.c
>> +
>> +# Using `-gt` generates full-fledged CTF debug information.
>> +set opts "additional_flags=-gt -Wl,--export-dynamic"
>> +if { [prepare_for_testing "failed to prepare" ${testfile} \
>> +	  [list $srcfile $srcfile2 $srcfile3 $srcfile4] \
>> +	  [list $opts nowarnings]] } {
>> +    return 0
>> +}
>> +
>> +# Create and source the file that provides information about the compiler
>> +# used to compile the test case.
>> +if [get_compiler_info] {
>> +    return -1
>> +}
>> +
>> +# Same thing with struct and union.
>> +gdb_test "ptype struct A" "type = struct A \{\[\r\n\]+\[ \t\]+long a;\[\r\n\]+\[ \t\]+struct B \\*foo;\[\r\n\]+\}.*" "ptype structure A"
>> +gdb_test "ptype struct B" "type = struct B \{\[\r\n\]+\[ \t\]+int foo;\[\r\n\]+\[ \t\]+struct A \\*bar;\[\r\n\]+\}.*" "ptype structure B"
>> +gdb_test "ptype struct C" "type = struct C \{\[\r\n\]+\[ \t\]+struct B \\*foo;\[\r\n\]+\[ \t\]+int b;\[\r\n\]+\}.*" "ptype structure C"
> The 3 previous lines have trailing spaces.

OK, will fix them.

>> diff --git a/gdb/testsuite/gdb.ctf/ctf-a.c b/gdb/testsuite/gdb.ctf/ctf-a.c
>> new file mode 100644
>> index 0000000..f514a33
>> --- /dev/null
>> +++ b/gdb/testsuite/gdb.ctf/ctf-a.c
>> @@ -0,0 +1,32 @@
>> +/* This test program is part of GDB, the GNU debugger.
>> +
>> +   Copyright 2021 Free Software Foundation, Inc.
>> +
>> +   This program is free software; you can redistribute it and/or modify
>> +   it under the terms of the GNU General Public License as published by
>> +   the Free Software Foundation; either version 3 of the License, or
>> +   (at your option) any later version.
>> +
>> +   This program is distributed in the hope that it will be useful,
>> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
>> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>> +   GNU General Public License for more details.
>> +
>> +   You should have received a copy of the GNU General Public License
>> +   along with this program.  If not, see <https://urldefense.com/v3/__http://www.gnu.org/licenses/__;!!GqivPVa7Brio!MlnQ4nwBBbhjsCOlrkvxnKDpvrQ5BtDctjA14y8Sh72MPt3sVujLIe8lqYzl-as2$ >.  */
>> +
>> +#include "ctf-a.h"
>> +
>> +static struct A a __attribute__((used));
>> +
>> +extern struct C *foo ();
>> +extern int bar ();
>> +
>> +int main ()
>> +{
>> +  struct C *cp;
>> +  cp = foo ();
>> +  if (cp)
> Trailing space.

Will fix it.

>> +    return bar ();
>> +  return 0;
>> +}
>> diff --git a/gdb/testsuite/gdb.ctf/ctf-a.h b/gdb/testsuite/gdb.ctf/ctf-a.h
>> new file mode 100644
>> index 0000000..297d740
>> --- /dev/null
>> +++ b/gdb/testsuite/gdb.ctf/ctf-a.h
>> @@ -0,0 +1,22 @@
>> +/* This test program is part of GDB, the GNU debugger.
>> +
>> +   Copyright 2021 Free Software Foundation, Inc.
>> +
>> +   This program is free software; you can redistribute it and/or modify
>> +   it under the terms of the GNU General Public License as published by
>> +   the Free Software Foundation; either version 3 of the License, or
>> +   (at your option) any later version.
>> +
>> +   This program is distributed in the hope that it will be useful,
>> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
>> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>> +   GNU General Public License for more details.
>> +
>> +   You should have received a copy of the GNU General Public License
>> +   along with this program.  If not, see <https://urldefense.com/v3/__http://www.gnu.org/licenses/__;!!GqivPVa7Brio!MlnQ4nwBBbhjsCOlrkvxnKDpvrQ5BtDctjA14y8Sh72MPt3sVujLIe8lqYzl-as2$ >.  */
>> +
>> +struct A {
>> +  struct B *b;
>> +  struct A *next;
>> +};
>> +
>> diff --git a/gdb/testsuite/gdb.ctf/ctf-b.c b/gdb/testsuite/gdb.ctf/ctf-b.c
>> new file mode 100644
>> index 0000000..c3a8ce5
>> --- /dev/null
>> +++ b/gdb/testsuite/gdb.ctf/ctf-b.c
>> @@ -0,0 +1,25 @@
>> +/* This test program is part of GDB, the GNU debugger.
>> +
>> +   Copyright 2021 Free Software Foundation, Inc.
>> +
>> +   This program is free software; you can redistribute it and/or modify
>> +   it under the terms of the GNU General Public License as published by
>> +   the Free Software Foundation; either version 3 of the License, or
>> +   (at your option) any later version.
>> +
>> +   This program is distributed in the hope that it will be useful,
>> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
>> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>> +   GNU General Public License for more details.
>> +
>> +   You should have received a copy of the GNU General Public License
>> +   along with this program.  If not, see <https://urldefense.com/v3/__http://www.gnu.org/licenses/__;!!GqivPVa7Brio!MlnQ4nwBBbhjsCOlrkvxnKDpvrQ5BtDctjA14y8Sh72MPt3sVujLIe8lqYzl-as2$ >.  */
>> +
>> +#include "ctf-b.h"
>> +
>> +static struct B b __attribute__((used));
>> +
>> +int bar ()
>> +{
>> +  return b.wombat;
>> +}
>> diff --git a/gdb/testsuite/gdb.ctf/ctf-b.h b/gdb/testsuite/gdb.ctf/ctf-b.h
>> new file mode 100644
>> index 0000000..9dbdd7d
>> --- /dev/null
>> +++ b/gdb/testsuite/gdb.ctf/ctf-b.h
>> @@ -0,0 +1,22 @@
>> +/* This test program is part of GDB, the GNU debugger.
>> +
>> +   Copyright 2021 Free Software Foundation, Inc.
>> +
>> +   This program is free software; you can redistribute it and/or modify
>> +   it under the terms of the GNU General Public License as published by
>> +   the Free Software Foundation; either version 3 of the License, or
>> +   (at your option) any later version.
>> +
>> +   This program is distributed in the hope that it will be useful,
>> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
>> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>> +   GNU General Public License for more details.
>> +
>> +   You should have received a copy of the GNU General Public License
>> +   along with this program.  If not, see <https://urldefense.com/v3/__http://www.gnu.org/licenses/__;!!GqivPVa7Brio!MlnQ4nwBBbhjsCOlrkvxnKDpvrQ5BtDctjA14y8Sh72MPt3sVujLIe8lqYzl-as2$ >.  */
>> +
>> +struct B {
>> +  struct C *c;
>> +  int wombat;
>> +};
>> +
>> diff --git a/gdb/testsuite/gdb.ctf/ctf-c.c b/gdb/testsuite/gdb.ctf/ctf-c.c
>> new file mode 100644
>> index 0000000..50db511
>> --- /dev/null
>> +++ b/gdb/testsuite/gdb.ctf/ctf-c.c
>> @@ -0,0 +1,25 @@
>> +/* This test program is part of GDB, the GNU debugger.
>> +
>> +   Copyright 2021 Free Software Foundation, Inc.
>> +
>> +   This program is free software; you can redistribute it and/or modify
>> +   it under the terms of the GNU General Public License as published by
>> +   the Free Software Foundation; either version 3 of the License, or
>> +   (at your option) any later version.
>> +
>> +   This program is distributed in the hope that it will be useful,
>> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
>> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>> +   GNU General Public License for more details.
>> +
>> +   You should have received a copy of the GNU General Public License
>> +   along with this program.  If not, see <https://urldefense.com/v3/__http://www.gnu.org/licenses/__;!!GqivPVa7Brio!MlnQ4nwBBbhjsCOlrkvxnKDpvrQ5BtDctjA14y8Sh72MPt3sVujLIe8lqYzl-as2$ >.  */
>> +
>> +#include "ctf-c.h"
>> +
>> +static struct C c __attribute__((used));
>> +
>> +struct C * foo ()
>> +{
>> +  return &c;
>> +}
> Trailing space

Will fix it.

>> diff --git a/gdb/testsuite/gdb.ctf/ctf-c.h b/gdb/testsuite/gdb.ctf/ctf-c.h
>> new file mode 100644
>> index 0000000..fb18157
>> --- /dev/null
>> +++ b/gdb/testsuite/gdb.ctf/ctf-c.h
>> @@ -0,0 +1,21 @@
>> +/* This test program is part of GDB, the GNU debugger.
>> +
>> +   Copyright 2021 Free Software Foundation, Inc.
>> +
>> +   This program is free software; you can redistribute it and/or modify
>> +   it under the terms of the GNU General Public License as published by
>> +   the Free Software Foundation; either version 3 of the License, or
>> +   (at your option) any later version.
>> +
>> +   This program is distributed in the hope that it will be useful,
>> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
>> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>> +   GNU General Public License for more details.
>> +
>> +   You should have received a copy of the GNU General Public License
>> +   along with this program.  If not, see <https://urldefense.com/v3/__http://www.gnu.org/licenses/__;!!GqivPVa7Brio!MlnQ4nwBBbhjsCOlrkvxnKDpvrQ5BtDctjA14y8Sh72MPt3sVujLIe8lqYzl-as2$ >.  */
>> +
>> +struct C {
>> +  struct A *a;
>> +  int b;
>> +};
>> diff --git a/gdb/testsuite/gdb.ctf/multi.exp b/gdb/testsuite/gdb.ctf/multi.exp
>> new file mode 100644
>> index 0000000..8e99f23
>> --- /dev/null
>> +++ b/gdb/testsuite/gdb.ctf/multi.exp
>> @@ -0,0 +1,42 @@
>> +# Copyright 2021 Free Software Foundation, Inc.
>> +
>> +# This program is free software; you can redistribute it and/or modify
>> +# it under the terms of the GNU General Public License as published by
>> +# the Free Software Foundation; either version 3 of the License, or
>> +# (at your option) any later version.
>> +#
>> +# This program is distributed in the hope that it will be useful,
>> +# but WITHOUT ANY WARRANTY; without even the implied warranty of
>> +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>> +# GNU General Public License for more details.
>> +#
>> +# You should have received a copy of the GNU General Public License
>> +# along with this program.  If not, see <https://urldefense.com/v3/__http://www.gnu.org/licenses/__;!!GqivPVa7Brio!MlnQ4nwBBbhjsCOlrkvxnKDpvrQ5BtDctjA14y8Sh72MPt3sVujLIe8lqYzl-as2$ >.
>> +
>> +# This file is a subset of ptype.exp written by Rob Savoye. (rob@cygnus.com)
>> +
>> +if [skip_ctf_tests] {
>> +    unsupported "no CTF debug format support, or CTF disabled in GDB"
>> +    return 0
>> +}
>> +
>> +standard_testfile ctf-a.c ctf-b.c ctf-c.c
>> +
>> +# Using `-gt` generates full-fledged CTF debug information.
>> +set opts "additional_flags=-gt -Wl,--export-dynamic"
>> +if { [prepare_for_testing "failed to prepare" ${testfile} \
>> +	  [list $srcfile $srcfile2 $srcfile3] \
>> +	  [list $opts nowarnings]] } {
>> +    return 0
>> +}
>> +
>> +# Create and source the file that provides information about the compiler
>> +# used to compile the test case.
>> +if [get_compiler_info] {
>> +    return -1
>> +}
>> +
>> +# Same thing with struct and union.
>> +gdb_test "ptype struct A" "type = struct A \{\[\r\n\]+\[ \t\]+struct B \\*b;\[\r\n\]+\[ \t\]+struct A \\*next;\[\r\n\]+\}.*" "ptype structure A"
>> +gdb_test "ptype struct B" "type = struct B \{\[\r\n\]+\[ \t\]+struct C \\*c;\[\r\n\]+\[ \t\]+int \\wombat;\[\r\n\]+\}.*" "ptype structure B"
>> +gdb_test "ptype struct C" "type = struct C \{\[\r\n\]+\[ \t\]+struct A \\*a;\[\r\n\]+\[ \t\]+int b;\[\r\n\]+\}.*" "ptype structure C"
> You also have trailing spaces here.

Will fix them.

Thanks very much for your comments.

>
> Lancelot.
>
>> -- 
>> 1.8.3.1
>>