[PATCH] PR ld/20828: Move symbol version processing ahead of GC symbol sweep
Maciej W. Rozycki
macro@imgtec.com
Wed Feb 1 19:31:00 GMT 2017
Complement commit b531344c34b0 ("PR ld/20828: Reorder the symbol sweep
stage of section GC") and commit 81ff47b3a546 ("PR ld/20828: Fix linker
script symbols wrongly forced local with section GC") and move symbol
version processing ahead of the symbol sweep stage of section GC, all in
`bfd_elf_size_dynamic_sections', so that version symbols created stay in
the global scope and are not output as local symbols to the dynamic symbol
table in the presence of corresponding symbol definitions pulled from a
DSO involved in a link.
Consolidate the whole of symbol version processing into a single block
from all parts scattered across the function and rearranging the local
variables used as necessary, however leaving the setting of dynamic
entries associated with the DT_VERDEF, DT_VERDEFNUM, DT_VERNEED and
DT_VERNEEDNUM tags in the original places.
With the rearrangement of code blocks `Elf_Internal_Verneed *t' would
shadow the previous definition of `struct bfd_elf_version_tree *t', so
rename the former variable to `vn'.
bfd/
PR ld/20828
* elflink.c (bfd_elf_size_dynamic_sections): Move symbol version
processing ahead of the call to `elf_gc_sweep_symbol'.
ld/
PR ld/20828
* testsuite/ld-elf/pr20828-d.sd: New test.
* testsuite/ld-elf/pr20828-e.sd: New test.
* testsuite/ld-elf/pr20828-v.ver: New test version script.
* testsuite/ld-elf/pr20828.ld: Add `.gnu.version' and
`.gnu.version_d'.
* testsuite/ld-elf/shared.exp: Run the new tests.
---
I had to do a little bit of thinking to figure out how to verify across
all targets that this somewhat radical change does not cause any bad
interaction between version processing in `bfd_elf_size_dynamic_sections'
and the two backend methods (`->elf_backend_always_size_sections' and
`->elf_backend_size_dynamic_sections') called midway through. So I asked
myself what could actually cause a problem here and eventually came to a
conclusion that the only scenario I can think of is where one of the
methods adds an exported symbol which currently goes through the usual
version processing, but would not anymore after this change.
To check if that is the case I have extracted, with the aid of a
combination of usual *nix text processing tools, all the methods and
looked through them for symbol creation. And indeed a couple do, namely:
`elf32_arm_always_size_sections', `elfNN_aarch64_always_size_sections'
`elf_i386_always_size_sections', `elf_x86_64_always_size_sections', and
`elf_xtensa_always_size_sections', all of which add an _TLS_MODULE_BASE_
symbol, which however has a local scope and is made hidden right away, so
it does get any interesting changes applied through version script
processing.
And that was just it. So it appears to me we should be safe with my
proposed fix unless there's something particularly peculiar somewhere that
I have missed (which would not be unheard of, as for example it was with
the S+core target earlier on in the course of addressing this PR). I have
got good regression test results across my current set of 175 targets
though, which are reassuring in that at least this change does not break
something we have previously recognised.
In addition to that, prompted by the `cris-elf' ld-cris/libdso-12c.d and
ld-cris/libdso-13b.d tests I have cowardly decided to keep the order of
dynamic entries produced unchanged, in case a third-party piece of
software relies on it (even though it shouldn't), and therefore I have
moved the creation of the 4 types used with symbol versioning (VERDEF,
VERDEFNUM, VERNEED, VERNEEDNUM) away from the calculations of the
corresponding values and down towards the end of the function where they
are currently made. There's no harm from doing that IMO, even if only to
satisfy human readers who may have got used over the years to how the
entries have been ordered in dumps.
Unfortunately due to how `diff' decided to record the changes the patch
looks more complicated than it really is, as the parts which I *haven't*
moved are shown rather than those I did move. So to look what has changed
it may be easier to visually compare the unchanged vs updated version of
`bfd_elf_size_dynamic_sections' side by side.
I do hope I haven't missed anything then, but I will be happy to address
any concerns this proposal may raise. Otherwise, OK to apply to master?
Maciej
binutils-bfd-elf-size-dynamic-sections-version.diff
Index: binutils/bfd/elflink.c
===================================================================
--- binutils.orig/bfd/elflink.c 2017-01-30 22:51:09.000000000 +0000
+++ binutils/bfd/elflink.c 2017-01-31 04:04:19.446661678 +0000
@@ -5925,7 +5925,6 @@ bfd_elf_size_dynamic_sections (bfd *outp
size_t soname_indx;
bfd *dynobj;
const struct elf_backend_data *bed;
- struct elf_info_failed asvinfo;
*sinterpptr = NULL;
@@ -5934,188 +5933,17 @@ bfd_elf_size_dynamic_sections (bfd *outp
if (!is_elf_hash_table (info->hash))
return TRUE;
- bed = get_elf_backend_data (output_bfd);
-
- if (info->gc_sections && bed->can_gc_sections)
- {
- struct elf_gc_sweep_symbol_info sweep_info;
- unsigned long section_sym_count;
-
- /* Remove the symbols that were in the swept sections from the
- dynamic symbol table. GCFIXME: Anyone know how to get them
- out of the static symbol table as well? */
- sweep_info.info = info;
- sweep_info.hide_symbol = bed->elf_backend_hide_symbol;
- elf_link_hash_traverse (elf_hash_table (info), elf_gc_sweep_symbol,
- &sweep_info);
-
- _bfd_elf_link_renumber_dynsyms (output_bfd, info, §ion_sym_count);
- }
-
- /* Any syms created from now on start with -1 in
- got.refcount/offset and plt.refcount/offset. */
- elf_hash_table (info)->init_got_refcount
- = elf_hash_table (info)->init_got_offset;
- elf_hash_table (info)->init_plt_refcount
- = elf_hash_table (info)->init_plt_offset;
-
- if (bfd_link_relocatable (info)
- && !_bfd_elf_size_group_sections (info))
- return FALSE;
-
- /* The backend may have to create some sections regardless of whether
- we're dynamic or not. */
- if (bed->elf_backend_always_size_sections
- && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
- return FALSE;
-
- /* Determine any GNU_STACK segment requirements, after the backend
- has had a chance to set a default segment size. */
- if (info->execstack)
- elf_stack_flags (output_bfd) = PF_R | PF_W | PF_X;
- else if (info->noexecstack)
- elf_stack_flags (output_bfd) = PF_R | PF_W;
- else
- {
- bfd *inputobj;
- asection *notesec = NULL;
- int exec = 0;
-
- for (inputobj = info->input_bfds;
- inputobj;
- inputobj = inputobj->link.next)
- {
- asection *s;
-
- if (inputobj->flags
- & (DYNAMIC | EXEC_P | BFD_PLUGIN | BFD_LINKER_CREATED))
- continue;
- s = bfd_get_section_by_name (inputobj, ".note.GNU-stack");
- if (s)
- {
- if (s->flags & SEC_CODE)
- exec = PF_X;
- notesec = s;
- }
- else if (bed->default_execstack)
- exec = PF_X;
- }
- if (notesec || info->stacksize > 0)
- elf_stack_flags (output_bfd) = PF_R | PF_W | exec;
- if (notesec && exec && bfd_link_relocatable (info)
- && notesec->output_section != bfd_abs_section_ptr)
- notesec->output_section->flags |= SEC_CODE;
- }
-
dynobj = elf_hash_table (info)->dynobj;
if (dynobj != NULL && elf_hash_table (info)->dynamic_sections_created)
{
- struct elf_info_failed eif;
- struct elf_link_hash_entry *h;
- asection *dynstr;
+ struct bfd_elf_version_tree *verdefs;
+ unsigned long section_sym_count;
+ struct elf_info_failed asvinfo;
struct bfd_elf_version_tree *t;
struct bfd_elf_version_expr *d;
- asection *s;
bfd_boolean all_defined;
-
- *sinterpptr = bfd_get_linker_section (dynobj, ".interp");
- BFD_ASSERT (*sinterpptr != NULL || !bfd_link_executable (info) || info->nointerp);
-
- if (soname != NULL)
- {
- soname_indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
- soname, TRUE);
- if (soname_indx == (size_t) -1
- || !_bfd_elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
- return FALSE;
- }
-
- if (info->symbolic)
- {
- if (!_bfd_elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
- return FALSE;
- info->flags |= DF_SYMBOLIC;
- }
-
- if (rpath != NULL)
- {
- size_t indx;
- bfd_vma tag;
-
- indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, rpath,
- TRUE);
- if (indx == (size_t) -1)
- return FALSE;
-
- tag = info->new_dtags ? DT_RUNPATH : DT_RPATH;
- if (!_bfd_elf_add_dynamic_entry (info, tag, indx))
- return FALSE;
- }
-
- if (filter_shlib != NULL)
- {
- size_t indx;
-
- indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
- filter_shlib, TRUE);
- if (indx == (size_t) -1
- || !_bfd_elf_add_dynamic_entry (info, DT_FILTER, indx))
- return FALSE;
- }
-
- if (auxiliary_filters != NULL)
- {
- const char * const *p;
-
- for (p = auxiliary_filters; *p != NULL; p++)
- {
- size_t indx;
-
- indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
- *p, TRUE);
- if (indx == (size_t) -1
- || !_bfd_elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
- return FALSE;
- }
- }
-
- if (audit != NULL)
- {
- size_t indx;
-
- indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, audit,
- TRUE);
- if (indx == (size_t) -1
- || !_bfd_elf_add_dynamic_entry (info, DT_AUDIT, indx))
- return FALSE;
- }
-
- if (depaudit != NULL)
- {
- size_t indx;
-
- indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, depaudit,
- TRUE);
- if (indx == (size_t) -1
- || !_bfd_elf_add_dynamic_entry (info, DT_DEPAUDIT, indx))
- return FALSE;
- }
-
- eif.info = info;
- eif.failed = FALSE;
-
- /* If we are supposed to export all symbols into the dynamic symbol
- table (this is not the normal case), then do so. */
- if (info->export_dynamic
- || (bfd_link_executable (info) && info->dynamic))
- {
- elf_link_hash_traverse (elf_hash_table (info),
- _bfd_elf_export_symbol,
- &eif);
- if (eif.failed)
- return FALSE;
- }
+ asection *s;
/* Make all global versions with definition. */
for (t = info->version_info; t != NULL; t = t->next)
@@ -6200,129 +6028,6 @@ bfd_elf_size_dynamic_sections (bfd *outp
}
}
- /* Find all symbols which were defined in a dynamic object and make
- the backend pick a reasonable value for them. */
- elf_link_hash_traverse (elf_hash_table (info),
- _bfd_elf_adjust_dynamic_symbol,
- &eif);
- if (eif.failed)
- return FALSE;
-
- /* Add some entries to the .dynamic section. We fill in some of the
- values later, in bfd_elf_final_link, but we must add the entries
- now so that we know the final size of the .dynamic section. */
-
- /* If there are initialization and/or finalization functions to
- call then add the corresponding DT_INIT/DT_FINI entries. */
- h = (info->init_function
- ? elf_link_hash_lookup (elf_hash_table (info),
- info->init_function, FALSE,
- FALSE, FALSE)
- : NULL);
- if (h != NULL
- && (h->ref_regular
- || h->def_regular))
- {
- if (!_bfd_elf_add_dynamic_entry (info, DT_INIT, 0))
- return FALSE;
- }
- h = (info->fini_function
- ? elf_link_hash_lookup (elf_hash_table (info),
- info->fini_function, FALSE,
- FALSE, FALSE)
- : NULL);
- if (h != NULL
- && (h->ref_regular
- || h->def_regular))
- {
- if (!_bfd_elf_add_dynamic_entry (info, DT_FINI, 0))
- return FALSE;
- }
-
- s = bfd_get_section_by_name (output_bfd, ".preinit_array");
- if (s != NULL && s->linker_has_input)
- {
- /* DT_PREINIT_ARRAY is not allowed in shared library. */
- if (! bfd_link_executable (info))
- {
- bfd *sub;
- asection *o;
-
- for (sub = info->input_bfds; sub != NULL;
- sub = sub->link.next)
- if (bfd_get_flavour (sub) == bfd_target_elf_flavour)
- for (o = sub->sections; o != NULL; o = o->next)
- if (elf_section_data (o)->this_hdr.sh_type
- == SHT_PREINIT_ARRAY)
- {
- _bfd_error_handler
- (_("%B: .preinit_array section is not allowed in DSO"),
- sub);
- break;
- }
-
- bfd_set_error (bfd_error_nonrepresentable_section);
- return FALSE;
- }
-
- if (!_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAY, 0)
- || !_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAYSZ, 0))
- return FALSE;
- }
- s = bfd_get_section_by_name (output_bfd, ".init_array");
- if (s != NULL && s->linker_has_input)
- {
- if (!_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAY, 0)
- || !_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAYSZ, 0))
- return FALSE;
- }
- s = bfd_get_section_by_name (output_bfd, ".fini_array");
- if (s != NULL && s->linker_has_input)
- {
- if (!_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAY, 0)
- || !_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAYSZ, 0))
- return FALSE;
- }
-
- dynstr = bfd_get_linker_section (dynobj, ".dynstr");
- /* If .dynstr is excluded from the link, we don't want any of
- these tags. Strictly, we should be checking each section
- individually; This quick check covers for the case where
- someone does a /DISCARD/ : { *(*) }. */
- if (dynstr != NULL && dynstr->output_section != bfd_abs_section_ptr)
- {
- bfd_size_type strsize;
-
- strsize = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
- if ((info->emit_hash
- && !_bfd_elf_add_dynamic_entry (info, DT_HASH, 0))
- || (info->emit_gnu_hash
- && !_bfd_elf_add_dynamic_entry (info, DT_GNU_HASH, 0))
- || !_bfd_elf_add_dynamic_entry (info, DT_STRTAB, 0)
- || !_bfd_elf_add_dynamic_entry (info, DT_SYMTAB, 0)
- || !_bfd_elf_add_dynamic_entry (info, DT_STRSZ, strsize)
- || !_bfd_elf_add_dynamic_entry (info, DT_SYMENT,
- bed->s->sizeof_sym))
- return FALSE;
- }
- }
-
- if (! _bfd_elf_maybe_strip_eh_frame_hdr (info))
- return FALSE;
-
- /* The backend must work out the sizes of all the other dynamic
- sections. */
- if (dynobj != NULL
- && bed->elf_backend_size_dynamic_sections != NULL
- && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
- return FALSE;
-
- if (dynobj != NULL && elf_hash_table (info)->dynamic_sections_created)
- {
- unsigned long section_sym_count;
- struct bfd_elf_version_tree *verdefs;
- asection *s;
-
/* Set up the version definition section. */
s = bfd_get_linker_section (dynobj, ".gnu.version_d");
BFD_ASSERT (s != NULL);
@@ -6341,7 +6046,6 @@ bfd_elf_size_dynamic_sections (bfd *outp
{
unsigned int cdefs;
bfd_size_type size;
- struct bfd_elf_version_tree *t;
bfd_byte *p;
Elf_Internal_Verdef def;
Elf_Internal_Verdaux defaux;
@@ -6557,34 +6261,9 @@ bfd_elf_size_dynamic_sections (bfd *outp
}
}
- if (!_bfd_elf_add_dynamic_entry (info, DT_VERDEF, 0)
- || !_bfd_elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
- return FALSE;
-
elf_tdata (output_bfd)->cverdefs = cdefs;
}
- if ((info->new_dtags && info->flags) || (info->flags & DF_STATIC_TLS))
- {
- if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS, info->flags))
- return FALSE;
- }
- else if (info->flags & DF_BIND_NOW)
- {
- if (!_bfd_elf_add_dynamic_entry (info, DT_BIND_NOW, 0))
- return FALSE;
- }
-
- if (info->flags_1)
- {
- if (bfd_link_executable (info))
- info->flags_1 &= ~ (DF_1_INITFIRST
- | DF_1_NODELETE
- | DF_1_NOOPEN);
- if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS_1, info->flags_1))
- return FALSE;
- }
-
/* Work out the size of the version reference section. */
s = bfd_get_linker_section (dynobj, ".gnu.version_r");
@@ -6608,7 +6287,7 @@ bfd_elf_size_dynamic_sections (bfd *outp
s->flags |= SEC_EXCLUDE;
else
{
- Elf_Internal_Verneed *t;
+ Elf_Internal_Verneed *vn;
unsigned int size;
unsigned int crefs;
bfd_byte *p;
@@ -6616,15 +6295,15 @@ bfd_elf_size_dynamic_sections (bfd *outp
/* Build the version dependency section. */
size = 0;
crefs = 0;
- for (t = elf_tdata (output_bfd)->verref;
- t != NULL;
- t = t->vn_nextref)
+ for (vn = elf_tdata (output_bfd)->verref;
+ vn != NULL;
+ vn = vn->vn_nextref)
{
Elf_Internal_Vernaux *a;
size += sizeof (Elf_External_Verneed);
++crefs;
- for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
+ for (a = vn->vn_auxptr; a != NULL; a = a->vna_nextptr)
size += sizeof (Elf_External_Vernaux);
}
@@ -6634,40 +6313,40 @@ bfd_elf_size_dynamic_sections (bfd *outp
return FALSE;
p = s->contents;
- for (t = elf_tdata (output_bfd)->verref;
- t != NULL;
- t = t->vn_nextref)
+ for (vn = elf_tdata (output_bfd)->verref;
+ vn != NULL;
+ vn = vn->vn_nextref)
{
unsigned int caux;
Elf_Internal_Vernaux *a;
size_t indx;
caux = 0;
- for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
+ for (a = vn->vn_auxptr; a != NULL; a = a->vna_nextptr)
++caux;
- t->vn_version = VER_NEED_CURRENT;
- t->vn_cnt = caux;
+ vn->vn_version = VER_NEED_CURRENT;
+ vn->vn_cnt = caux;
indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
- elf_dt_name (t->vn_bfd) != NULL
- ? elf_dt_name (t->vn_bfd)
- : lbasename (t->vn_bfd->filename),
+ elf_dt_name (vn->vn_bfd) != NULL
+ ? elf_dt_name (vn->vn_bfd)
+ : lbasename (vn->vn_bfd->filename),
FALSE);
if (indx == (size_t) -1)
return FALSE;
- t->vn_file = indx;
- t->vn_aux = sizeof (Elf_External_Verneed);
- if (t->vn_nextref == NULL)
- t->vn_next = 0;
+ vn->vn_file = indx;
+ vn->vn_aux = sizeof (Elf_External_Verneed);
+ if (vn->vn_nextref == NULL)
+ vn->vn_next = 0;
else
- t->vn_next = (sizeof (Elf_External_Verneed)
+ vn->vn_next = (sizeof (Elf_External_Verneed)
+ caux * sizeof (Elf_External_Vernaux));
- _bfd_elf_swap_verneed_out (output_bfd, t,
+ _bfd_elf_swap_verneed_out (output_bfd, vn,
(Elf_External_Verneed *) p);
p += sizeof (Elf_External_Verneed);
- for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
+ for (a = vn->vn_auxptr; a != NULL; a = a->vna_nextptr)
{
a->vna_hash = bfd_elf_hash (a->vna_nodename);
indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
@@ -6686,10 +6365,6 @@ bfd_elf_size_dynamic_sections (bfd *outp
}
}
- if (!_bfd_elf_add_dynamic_entry (info, DT_VERNEED, 0)
- || !_bfd_elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
- return FALSE;
-
elf_tdata (output_bfd)->cverrefs = crefs;
}
}
@@ -6703,6 +6378,343 @@ bfd_elf_size_dynamic_sections (bfd *outp
s->flags |= SEC_EXCLUDE;
}
}
+
+ bed = get_elf_backend_data (output_bfd);
+
+ if (info->gc_sections && bed->can_gc_sections)
+ {
+ struct elf_gc_sweep_symbol_info sweep_info;
+ unsigned long section_sym_count;
+
+ /* Remove the symbols that were in the swept sections from the
+ dynamic symbol table. GCFIXME: Anyone know how to get them
+ out of the static symbol table as well? */
+ sweep_info.info = info;
+ sweep_info.hide_symbol = bed->elf_backend_hide_symbol;
+ elf_link_hash_traverse (elf_hash_table (info), elf_gc_sweep_symbol,
+ &sweep_info);
+
+ _bfd_elf_link_renumber_dynsyms (output_bfd, info, §ion_sym_count);
+ }
+
+ /* Any syms created from now on start with -1 in
+ got.refcount/offset and plt.refcount/offset. */
+ elf_hash_table (info)->init_got_refcount
+ = elf_hash_table (info)->init_got_offset;
+ elf_hash_table (info)->init_plt_refcount
+ = elf_hash_table (info)->init_plt_offset;
+
+ if (bfd_link_relocatable (info)
+ && !_bfd_elf_size_group_sections (info))
+ return FALSE;
+
+ /* The backend may have to create some sections regardless of whether
+ we're dynamic or not. */
+ if (bed->elf_backend_always_size_sections
+ && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
+ return FALSE;
+
+ /* Determine any GNU_STACK segment requirements, after the backend
+ has had a chance to set a default segment size. */
+ if (info->execstack)
+ elf_stack_flags (output_bfd) = PF_R | PF_W | PF_X;
+ else if (info->noexecstack)
+ elf_stack_flags (output_bfd) = PF_R | PF_W;
+ else
+ {
+ bfd *inputobj;
+ asection *notesec = NULL;
+ int exec = 0;
+
+ for (inputobj = info->input_bfds;
+ inputobj;
+ inputobj = inputobj->link.next)
+ {
+ asection *s;
+
+ if (inputobj->flags
+ & (DYNAMIC | EXEC_P | BFD_PLUGIN | BFD_LINKER_CREATED))
+ continue;
+ s = bfd_get_section_by_name (inputobj, ".note.GNU-stack");
+ if (s)
+ {
+ if (s->flags & SEC_CODE)
+ exec = PF_X;
+ notesec = s;
+ }
+ else if (bed->default_execstack)
+ exec = PF_X;
+ }
+ if (notesec || info->stacksize > 0)
+ elf_stack_flags (output_bfd) = PF_R | PF_W | exec;
+ if (notesec && exec && bfd_link_relocatable (info)
+ && notesec->output_section != bfd_abs_section_ptr)
+ notesec->output_section->flags |= SEC_CODE;
+ }
+
+ if (dynobj != NULL && elf_hash_table (info)->dynamic_sections_created)
+ {
+ struct elf_info_failed eif;
+ struct elf_link_hash_entry *h;
+ asection *dynstr;
+ asection *s;
+
+ *sinterpptr = bfd_get_linker_section (dynobj, ".interp");
+ BFD_ASSERT (*sinterpptr != NULL || !bfd_link_executable (info) || info->nointerp);
+
+ if (soname != NULL)
+ {
+ soname_indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
+ soname, TRUE);
+ if (soname_indx == (size_t) -1
+ || !_bfd_elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
+ return FALSE;
+ }
+
+ if (info->symbolic)
+ {
+ if (!_bfd_elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
+ return FALSE;
+ info->flags |= DF_SYMBOLIC;
+ }
+
+ if (rpath != NULL)
+ {
+ size_t indx;
+ bfd_vma tag;
+
+ indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, rpath,
+ TRUE);
+ if (indx == (size_t) -1)
+ return FALSE;
+
+ tag = info->new_dtags ? DT_RUNPATH : DT_RPATH;
+ if (!_bfd_elf_add_dynamic_entry (info, tag, indx))
+ return FALSE;
+ }
+
+ if (filter_shlib != NULL)
+ {
+ size_t indx;
+
+ indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
+ filter_shlib, TRUE);
+ if (indx == (size_t) -1
+ || !_bfd_elf_add_dynamic_entry (info, DT_FILTER, indx))
+ return FALSE;
+ }
+
+ if (auxiliary_filters != NULL)
+ {
+ const char * const *p;
+
+ for (p = auxiliary_filters; *p != NULL; p++)
+ {
+ size_t indx;
+
+ indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
+ *p, TRUE);
+ if (indx == (size_t) -1
+ || !_bfd_elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
+ return FALSE;
+ }
+ }
+
+ if (audit != NULL)
+ {
+ size_t indx;
+
+ indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, audit,
+ TRUE);
+ if (indx == (size_t) -1
+ || !_bfd_elf_add_dynamic_entry (info, DT_AUDIT, indx))
+ return FALSE;
+ }
+
+ if (depaudit != NULL)
+ {
+ size_t indx;
+
+ indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, depaudit,
+ TRUE);
+ if (indx == (size_t) -1
+ || !_bfd_elf_add_dynamic_entry (info, DT_DEPAUDIT, indx))
+ return FALSE;
+ }
+
+ eif.info = info;
+ eif.failed = FALSE;
+
+ /* If we are supposed to export all symbols into the dynamic symbol
+ table (this is not the normal case), then do so. */
+ if (info->export_dynamic
+ || (bfd_link_executable (info) && info->dynamic))
+ {
+ elf_link_hash_traverse (elf_hash_table (info),
+ _bfd_elf_export_symbol,
+ &eif);
+ if (eif.failed)
+ return FALSE;
+ }
+
+ /* Find all symbols which were defined in a dynamic object and make
+ the backend pick a reasonable value for them. */
+ elf_link_hash_traverse (elf_hash_table (info),
+ _bfd_elf_adjust_dynamic_symbol,
+ &eif);
+ if (eif.failed)
+ return FALSE;
+
+ /* Add some entries to the .dynamic section. We fill in some of the
+ values later, in bfd_elf_final_link, but we must add the entries
+ now so that we know the final size of the .dynamic section. */
+
+ /* If there are initialization and/or finalization functions to
+ call then add the corresponding DT_INIT/DT_FINI entries. */
+ h = (info->init_function
+ ? elf_link_hash_lookup (elf_hash_table (info),
+ info->init_function, FALSE,
+ FALSE, FALSE)
+ : NULL);
+ if (h != NULL
+ && (h->ref_regular
+ || h->def_regular))
+ {
+ if (!_bfd_elf_add_dynamic_entry (info, DT_INIT, 0))
+ return FALSE;
+ }
+ h = (info->fini_function
+ ? elf_link_hash_lookup (elf_hash_table (info),
+ info->fini_function, FALSE,
+ FALSE, FALSE)
+ : NULL);
+ if (h != NULL
+ && (h->ref_regular
+ || h->def_regular))
+ {
+ if (!_bfd_elf_add_dynamic_entry (info, DT_FINI, 0))
+ return FALSE;
+ }
+
+ s = bfd_get_section_by_name (output_bfd, ".preinit_array");
+ if (s != NULL && s->linker_has_input)
+ {
+ /* DT_PREINIT_ARRAY is not allowed in shared library. */
+ if (! bfd_link_executable (info))
+ {
+ bfd *sub;
+ asection *o;
+
+ for (sub = info->input_bfds; sub != NULL;
+ sub = sub->link.next)
+ if (bfd_get_flavour (sub) == bfd_target_elf_flavour)
+ for (o = sub->sections; o != NULL; o = o->next)
+ if (elf_section_data (o)->this_hdr.sh_type
+ == SHT_PREINIT_ARRAY)
+ {
+ _bfd_error_handler
+ (_("%B: .preinit_array section is not allowed in DSO"),
+ sub);
+ break;
+ }
+
+ bfd_set_error (bfd_error_nonrepresentable_section);
+ return FALSE;
+ }
+
+ if (!_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAY, 0)
+ || !_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAYSZ, 0))
+ return FALSE;
+ }
+ s = bfd_get_section_by_name (output_bfd, ".init_array");
+ if (s != NULL && s->linker_has_input)
+ {
+ if (!_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAY, 0)
+ || !_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAYSZ, 0))
+ return FALSE;
+ }
+ s = bfd_get_section_by_name (output_bfd, ".fini_array");
+ if (s != NULL && s->linker_has_input)
+ {
+ if (!_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAY, 0)
+ || !_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAYSZ, 0))
+ return FALSE;
+ }
+
+ dynstr = bfd_get_linker_section (dynobj, ".dynstr");
+ /* If .dynstr is excluded from the link, we don't want any of
+ these tags. Strictly, we should be checking each section
+ individually; This quick check covers for the case where
+ someone does a /DISCARD/ : { *(*) }. */
+ if (dynstr != NULL && dynstr->output_section != bfd_abs_section_ptr)
+ {
+ bfd_size_type strsize;
+
+ strsize = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
+ if ((info->emit_hash
+ && !_bfd_elf_add_dynamic_entry (info, DT_HASH, 0))
+ || (info->emit_gnu_hash
+ && !_bfd_elf_add_dynamic_entry (info, DT_GNU_HASH, 0))
+ || !_bfd_elf_add_dynamic_entry (info, DT_STRTAB, 0)
+ || !_bfd_elf_add_dynamic_entry (info, DT_SYMTAB, 0)
+ || !_bfd_elf_add_dynamic_entry (info, DT_STRSZ, strsize)
+ || !_bfd_elf_add_dynamic_entry (info, DT_SYMENT,
+ bed->s->sizeof_sym))
+ return FALSE;
+ }
+ }
+
+ if (! _bfd_elf_maybe_strip_eh_frame_hdr (info))
+ return FALSE;
+
+ /* The backend must work out the sizes of all the other dynamic
+ sections. */
+ if (dynobj != NULL
+ && bed->elf_backend_size_dynamic_sections != NULL
+ && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
+ return FALSE;
+
+ if (dynobj != NULL && elf_hash_table (info)->dynamic_sections_created)
+ {
+ if (elf_tdata (output_bfd)->cverdefs)
+ {
+ unsigned int crefs = elf_tdata (output_bfd)->cverdefs;
+
+ if (!_bfd_elf_add_dynamic_entry (info, DT_VERDEF, 0)
+ || !_bfd_elf_add_dynamic_entry (info, DT_VERDEFNUM, crefs))
+ return FALSE;
+ }
+
+ if ((info->new_dtags && info->flags) || (info->flags & DF_STATIC_TLS))
+ {
+ if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS, info->flags))
+ return FALSE;
+ }
+ else if (info->flags & DF_BIND_NOW)
+ {
+ if (!_bfd_elf_add_dynamic_entry (info, DT_BIND_NOW, 0))
+ return FALSE;
+ }
+
+ if (info->flags_1)
+ {
+ if (bfd_link_executable (info))
+ info->flags_1 &= ~ (DF_1_INITFIRST
+ | DF_1_NODELETE
+ | DF_1_NOOPEN);
+ if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS_1, info->flags_1))
+ return FALSE;
+ }
+
+ if (elf_tdata (output_bfd)->cverrefs)
+ {
+ unsigned int crefs = elf_tdata (output_bfd)->cverrefs;
+
+ if (!_bfd_elf_add_dynamic_entry (info, DT_VERNEED, 0)
+ || !_bfd_elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
+ return FALSE;
+ }
+ }
return TRUE;
}
Index: binutils/ld/testsuite/ld-elf/pr20828-d.sd
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ binutils/ld/testsuite/ld-elf/pr20828-d.sd 2017-01-31 14:46:30.926958068 +0000
@@ -0,0 +1,9 @@
+# Make sure `vdata' is global rather than local in the dynamic symbol table,
+# e.g.:
+# Num: Value Size Type Bind Vis Ndx Name
+# 1: 00000000 0 OBJECT GLOBAL DEFAULT ABS vdata
+# vs:
+# 1: 00000000 0 OBJECT LOCAL DEFAULT ABS vdata
+#...
+ *[0-9]+: +[0-9a-f]+ +0 +OBJECT +GLOBAL +DEFAULT +ABS +vdata
+#pass
Index: binutils/ld/testsuite/ld-elf/pr20828-e.sd
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ binutils/ld/testsuite/ld-elf/pr20828-e.sd 2017-01-31 15:16:59.078917392 +0000
@@ -0,0 +1,9 @@
+# Make sure `edata' is global rather than local in the dynamic symbol table,
+# e.g.:
+# Num: Value Size Type Bind Vis Ndx Name
+# 1: 00000000 0 NOTYPE GLOBAL DEFAULT 1 edata@@vdata
+# vs:
+# 1: 00000000 0 NOTYPE LOCAL DEFAULT 1 edata@@vdata
+#...
+ *[0-9]+: +[0-9a-f]+ +0 +NOTYPE +GLOBAL +DEFAULT +[0-9]+ +edata@@vdata
+#pass
Index: binutils/ld/testsuite/ld-elf/pr20828-v.ver
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ binutils/ld/testsuite/ld-elf/pr20828-v.ver 2017-01-31 14:46:31.242435021 +0000
@@ -0,0 +1 @@
+vdata { global: edata; local: *; };
Index: binutils/ld/testsuite/ld-elf/pr20828.ld
===================================================================
--- binutils.orig/ld/testsuite/ld-elf/pr20828.ld 2017-01-31 14:46:26.169112837 +0000
+++ binutils/ld/testsuite/ld-elf/pr20828.ld 2017-01-31 14:46:31.411858383 +0000
@@ -10,6 +10,8 @@ SECTIONS
.hash : { *(.hash) }
.dynsym : { *(.dynsym) }
.dynstr : { *(.dynstr) }
+ .gnu.version : { *(.gnu.version) }
+ .gnu.version_d : { *(.gnu.version_d) }
.shstrtab : { *(.shstrtab) }
.symtab : { *(.symtab) }
.strtab : { *(.strtab) }
Index: binutils/ld/testsuite/ld-elf/shared.exp
===================================================================
--- binutils.orig/ld/testsuite/ld-elf/shared.exp 2017-01-31 14:46:26.528721361 +0000
+++ binutils/ld/testsuite/ld-elf/shared.exp 2017-01-31 15:19:08.139588324 +0000
@@ -77,7 +77,30 @@ if { [check_gc_sections_available] } {
{pr20828.s} \
{{readelf --dyn-syms pr20828-b.sd} \
{readelf --dyn-syms pr20828-c.sd}} \
- "pr20828-2.so"]]
+ "pr20828-2.so"] \
+ [list \
+ "PR ld/20828 dynamic symbols with section GC\
+ (versioned shared library)" \
+ "$LFLAGS -shared --gc-sections -T pr20828.ld\
+ --version-script=pr20828-v.ver" \
+ "" "$AFLAGS_PIC" \
+ {pr20828.s} \
+ {{readelf --dyn-syms pr20828-c.sd} \
+ {readelf --dyn-syms pr20828-d.sd} \
+ {readelf --dyn-syms pr20828-e.sd}} \
+ "libpr20828-v.so"] \
+ [list \
+ "PR ld/20828 dynamic symbols with section GC (versioned)" \
+ "$LFLAGS -shared --gc-sections -T pr20828.ld\
+ --version-script=pr20828-v.ver" \
+ "tmpdir/libpr20828-v.so" \
+ "$AFLAGS_PIC" \
+ {pr20828.s} \
+ {{readelf --dyn-syms pr20828-c.sd} \
+ {readelf --dyn-syms pr20828-d.sd} \
+ {readelf --dyn-syms pr20828-e.sd}} \
+ "pr20828-v.so"] \
+ ]
}
# Check to see if the C compiler works
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