[PING 2][PATCH V5] CTF: multi-CU and archive support

Wei-min Pan via Gdb-patches
2021-06-02T00:06:11Z

On 5/24/2021 5:52 PM, Wei-min Pan wrote:
>
> On 5/17/2021 5:20 PM, Weimin Pan via Gdb-patches wrote:
>> [Changes from V4:
>>   - Treat CTF archives as CUs over dependencies to avoid over-expanding
>>     psymtabs, as Tom Tromey pointed out.
>>   - Avoid calling ctf_dict_close more than once on a dictionary.]
>>
>> Now gdb is capable of debugging executable, which consists of multiple
>> compilation units (CUs) with the CTF debug info. An executable could
>> potentially have one or more archives, which, in CTF context, contain
>> conflicting types.
>>
>> all changes were made in ctfread.c in which elfctf_build_psymtabs was
>> modified to handle archives, via the ctf archive iterator and its
>> callback
>> build_ctf_archive_member and scan_partial_symbols was modified to scan
>> archives, which are treated as subfiles, to build the psymtabs.
>>
>> Also changes were made to handle CTF's data object section and function
>> info section which now share the same format of 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/ctfread.c                             | 311
>> +++++++++++++++++-------------
>>   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 ++++
>>   13 files changed, 453 insertions(+), 131 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/ctfread.c b/gdb/ctfread.c
>> index 23e859a..1939f40 100644
>> --- a/gdb/ctfread.c
>> +++ b/gdb/ctfread.c
>> @@ -117,6 +117,7 @@ struct ctf_context
>>     struct objfile *of;
>>     psymtab_storage *partial_symtabs;
>>     partial_symtab *pst;
>> +  ctf_archive_t *arc;
>>     struct buildsym_compunit *builder;
>>   };
>>   @@ -166,6 +167,16 @@ struct ctf_field_info
>>     std::vector<struct decl_field> nested_types_list;
>>   };
>>   +/* Data held for a translation unit.  */
>> +
>> +struct ctf_per_tu_data
>> +{
>> +  ctf_dict_t *fp;
>> +  struct objfile *of;
>> +  ctf_archive_t *arc;
>> +  psymtab_storage *pss;
>> +  psymbol_functions *psf;
>> +};
>>     /* Local function prototypes */
>>   @@ -245,10 +256,8 @@ 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 == nullptr)
>> +    *slot = XOBNEW (&of->objfile_obstack, struct ctf_tid_and_type);
>>     **slot = ids;
>>     return typ;
>>   }
>> @@ -510,7 +519,7 @@ struct ctf_tid_and_type
>>           break;
>>       }
>>   -      add_symbol_to_list (sym, ccp->builder->get_global_symbols ());
>> +      add_symbol_to_list (sym, ccp->builder->get_file_symbols ());
>>       }
>>       return sym;
>> @@ -1143,7 +1152,8 @@ 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)
>> +          sym->compute_and_set_names (name, false, ccp->of->per_bfd);
>>         }
>>       break;
>>         case CTF_K_STRUCT:
>> @@ -1160,7 +1170,7 @@ struct ctf_tid_and_type
>>       SYMBOL_DOMAIN (sym) = VAR_DOMAIN;
>>       SYMBOL_ACLASS_INDEX (sym) = LOC_OPTIMIZED_OUT;
>>       sym->compute_and_set_names (name, false, ccp->of->per_bfd);
>> -    add_symbol_to_list (sym, ccp->builder->get_global_symbols ());
>> +    add_symbol_to_list (sym, ccp->builder->get_file_symbols ());
>>       break;
>>         default:
>>       complaint (_("ctf_add_var_cb: kind unsupported (%d)"), kind);
>> @@ -1173,81 +1183,48 @@ 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 = nullptr;
>> +  const char *tname;
>>     ctf_id_t tid;
>> +  struct symbol *sym = nullptr;
>> +  struct type *type;
>>   -  if ((tid = ctf_lookup_by_symbol (ccp->fp, idx)) == CTF_ERR)
>> -    return nullptr;
>> -
>> -  type = fetch_tid_type (ccp, tid);
>> -  if (type == nullptr)
>> -    return nullptr;
>> -
>> -  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 == nullptr)
>> +    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 nullptr;
>> -
>> -  argc = finfo.ctc_argc;
>> -  if (ctf_func_args (ccp->fp, idx, argc, argv) == CTF_ERR)
>> -    return nullptr;
>> -
>> -  gdb::unique_xmalloc_ptr<char> name (ctf_type_aname_raw (ccp->fp,
>> idx));
>> -  if (name == nullptr)
>> -    return nullptr;
>> -
>> -  tid = ctf_lookup_by_symbol (ccp->fp, idx);
>> -  ftype = fetch_tid_type (ccp, tid);
>> -  if ((finfo.ctc_flags & CTF_FUNC_VARARG) != 0)
>> -    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)));
>> -
>> -  /* 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_stt_entries (ccp, 0);
>> +}
>>   -  sym = new_symbol (ccp, ftype, tid);
>> -  rettyp = fetch_tid_type (ccp, finfo.ctc_return);
>> -  if (rettyp != nullptr)
>> -    SYMBOL_TYPE (sym) = rettyp;
>> -  else
>> -    SYMBOL_TYPE (sym) = void_type;
>> +/* Add entries in function info section.  */
>>   -  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.  */
>> @@ -1317,12 +1294,71 @@ 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 = nullptr;
>> +  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, pst->context->partial_symtabs, 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);
>> @@ -1341,21 +1377,8 @@ struct ctf_tid_and_type
>>              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 == nullptr)
>> -    {
>> -      if (ctf_errno (ccp->fp) == EINVAL
>> -          || ctf_errno (ccp->fp) == ECTF_NOSYMTAB)
>> -        break;
>> -      sym = add_stt_func (ccp, i);
>> -    }
>> -      if (sym == nullptr)
>> -    continue;
>> -
>> -      set_symbol_address (ccp->of, sym, sym->linkage_name ());
>> -    }
>> +  add_stt_obj (ccp);
>> +  add_stt_func (ccp);
>>       readin = true;
>>   }
>> @@ -1409,6 +1432,7 @@ struct ctf_tid_and_type
>>     static ctf_psymtab *
>>   create_partial_symtab (const char *name,
>> +               ctf_archive_t *arc,
>>                  ctf_dict_t *cfp,
>>                  psymtab_storage *partial_symtabs,
>>                  struct objfile *objfile)
>> @@ -1419,11 +1443,12 @@ struct ctf_tid_and_type
>>     pst = new ctf_psymtab (name, partial_symtabs, objfile->per_bfd, 0);
>>       ccx = XOBNEW (&objfile->objfile_obstack, struct ctf_context);
>> +  ccx->arc = arc;
>>     ccx->fp = cfp;
>> +  ctf_ref (cfp);
>>     ccx->of = objfile;
>>     ccx->partial_symtabs = partial_symtabs;
>>     ccx->pst = pst;
>> -  ccx->builder = nullptr;
>>     pst->context = ccx;
>>       return pst;
>> @@ -1486,7 +1511,7 @@ struct ctf_tid_and_type
>>       ccp->pst->add_psymbol (name, false,
>>                domain, aclass, section,
>> -             psymbol_placement::GLOBAL,
>> +             psymbol_placement::STATIC,
>>                0, language_c, ccp->partial_symtabs, ccp->of);
>>       return 0;
>> @@ -1506,18 +1531,46 @@ struct ctf_tid_and_type
>>     return 0;
>>   }
>>   +/* Start a subfile for CTF. FNAME is the name of the archive.  */
>> +
>> +static void
>> +ctf_start_archive (struct ctf_context *ccx, struct objfile *of,
>> +           const char *fname)
>> +{
>> +  if (ccx->builder == nullptr)
>> +    {
>> +      ccx->builder = new buildsym_compunit (of,
>> +              of->original_name, nullptr, language_c, 0);
>> +      ccx->builder->record_debugformat ("ctf");
>> +    }
>> +  ccx->builder->start_subfile (fname);
>> +}
>> +
>>   /* Setup partial_symtab's describing each source file for which
>>      debugging information is available.  */
>>     static void
>>   scan_partial_symbols (ctf_dict_t *cfp, psymtab_storage
>> *partial_symtabs,
>> -              struct objfile *of)
>> +              struct ctf_per_tu_data *tup, const char *fname)
>>   {
>> -  bfd *abfd = of->obfd;
>> -  const char *name = bfd_get_filename (abfd);
>> -  ctf_psymtab *pst = create_partial_symtab (name, cfp,
>> partial_symtabs, of);
>> +  struct objfile *of = tup->of;
>> +  bool isparent = false;
>> +
>> +  if (strcmp (fname, ".ctf") == 0)
>> +    {
>> +      fname = bfd_get_filename (of->obfd);
>> +      isparent = true;
>> +    }
>> +
>> +  ctf_psymtab *pst = create_partial_symtab (fname, tup->arc, cfp,
>> +                        partial_symtabs, of);
>>       struct ctf_context *ccx = pst->context;
>> +  if (isparent == false)
>> +    {
>> +      ctf_start_archive (ccx, of, fname);
>> +      ccx->pst = pst;
>> +    }
>>       if (ctf_type_iter (cfp, ctf_psymtab_type_cb, ccx) == CTF_ERR)
>>       complaint (_("ctf_type_iter scan_partial_symbols failed - %s"),
>> @@ -1530,46 +1583,33 @@ 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;
>> -    }
>> -      const char *tname = ctf_type_name_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, false,
>> -            tdomain, aclass, -1,
>> -            psymbol_placement::STATIC,
>> -            0, language_c, partial_symtabs, of);
>> +/* Callback to build the psymtab for archive member NAME.  */
>> +
>> +static int
>> +build_ctf_archive_member (ctf_dict_t *ctf, const char *name, void *arg)
>> +{
>> +  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);
>> +
>> +  if (info_verbose)
>> +    {
>> +      printf_filtered (_("Scanning archive member %s..."), name);
>> +      gdb_flush (gdb_stdout);
>>       }
>>   -  pst->end ();
>> +  psymtab_storage *pss = tup->psf->get_partial_symtabs ().get ();
>> +  scan_partial_symbols (ctf, pss, tup, name);
>> +
>> +  return 0;
>>   }
>>     /* Read CTF debugging information from a BFD section.  This is
>> @@ -1579,6 +1619,7 @@ struct ctf_tid_and_type
>>   void
>>   elfctf_build_psymtabs (struct objfile *of)
>>   {
>> +  struct ctf_per_tu_data pcu;
>>     bfd *abfd = of->obfd;
>>     int err;
>>   @@ -1593,10 +1634,18 @@ struct ctf_tid_and_type
>>          bfd_get_filename (abfd), ctf_errmsg (err));
>>     ctf_dict_key.emplace (of, fp);
>>   +  pcu.fp = fp;
>> +  pcu.of = of;
>> +  pcu.arc = arc;
>> +
>>     psymbol_functions *psf = new psymbol_functions ();
>>     psymtab_storage *partial_symtabs = psf->get_partial_symtabs
>> ().get ();
>>     of->qf.emplace_front (psf);
>> -  scan_partial_symbols (fp, partial_symtabs, of);
>> +  pcu.psf = psf;
>> +
>> +  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));
>>   }
>>     #else
>> 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..b6e640e
>> --- /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!KfrttasFsnIw1ZHq2B1VVTIQZbEXNf8botBC8BmTRvyeUnbHs4wvBeakioqQKyuK$
>> >.
>> +
>> +# 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 \{\[\r\n\]+\[ \t\]+struct
>> B \\*foo;\[\r\n\]+\}.*" "ptype structure A"
>> +gdb_test "ptype struct B" "type = struct B \{\[\r\n\]+\[ \t\]+struct
>> B \\*next;\[\r\n\]+\}.*" "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"
>> diff --git a/gdb/testsuite/gdb.ctf/ctf-a.c
>> b/gdb/testsuite/gdb.ctf/ctf-a.c
>> new file mode 100644
>> index 0000000..9aa2a8f
>> --- /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!KfrttasFsnIw1ZHq2B1VVTIQZbEXNf8botBC8BmTRvyeUnbHs4wvBeakioqQKyuK$
>> >.  */
>> +
>> +#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)
>> +    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!KfrttasFsnIw1ZHq2B1VVTIQZbEXNf8botBC8BmTRvyeUnbHs4wvBeakioqQKyuK$
>> >.  */
>> +
>> +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!KfrttasFsnIw1ZHq2B1VVTIQZbEXNf8botBC8BmTRvyeUnbHs4wvBeakioqQKyuK$
>> >.  */
>> +
>> +#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!KfrttasFsnIw1ZHq2B1VVTIQZbEXNf8botBC8BmTRvyeUnbHs4wvBeakioqQKyuK$
>> >.  */
>> +
>> +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..b4051b3
>> --- /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!KfrttasFsnIw1ZHq2B1VVTIQZbEXNf8botBC8BmTRvyeUnbHs4wvBeakioqQKyuK$
>> >.  */
>> +
>> +#include "ctf-c.h"
>> +
>> +static struct C c __attribute__((used));
>> +
>> +struct C * foo ()
>> +{
>> +  return &c;
>> +}
>> 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!KfrttasFsnIw1ZHq2B1VVTIQZbEXNf8botBC8BmTRvyeUnbHs4wvBeakioqQKyuK$
>> >.  */
>> +
>> +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..973115e
>> --- /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!KfrttasFsnIw1ZHq2B1VVTIQZbEXNf8botBC8BmTRvyeUnbHs4wvBeakioqQKyuK$
>> >.
>> +
>> +# 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"