From cbd0eecf261c2447781f8c89b0d955ee66fae7e9 Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Tue, 13 Jun 2017 08:53:22 -0700
Subject: [PATCH] Always define referenced __start_SECNAME/__stop_SECNAME

Currently, linker will define __start_SECNAME and __stop_SECNAME symbols
only for orphaned sections.

However, during garbage collection, ELF linker marks all sections with
references to __start_SECNAME and __stop_SECNAME symbols as used even
when section SECNAME isn't an orphaned section and linker won't define
__start_SECNAME nor __stop_SECNAME.  And ELF linker stores the first
input section whose name matches __start_SECNAME or __stop_SECNAME in
u.undef.section for garbage collection.  If these symbols are provided
in linker script, u.undef.section is set to the section where they will
defined by linker script, which leads to the incorrect output.

This patch changes linker to always define referenced __start_SECNAME and
__stop_SECNAME if the input section name is the same as the output section
name, which is always true for orphaned sections, and SECNAME is a C
identifier.  Also __start_SECNAME and __stop_SECNAME symbols are marked
as hidden by ELF linker so that __start_SECNAME and __stop_SECNAME symbols
for section SECNAME in different modules are unique.  For garbage
collection, ELF linker stores the first matched input section in the
unused vtable field.

bfd/

	PR ld/20022
	PR ld/21557
	PR ld/21562
	PR ld/21571
	* elf-bfd.h (elf_link_hash_entry): Add start_stop.  Change the
	vtable field to a union.
	(_bfd_elf_is_start_stop): Removed.
	* elf32-i386.c (elf_i386_convert_load_reloc): Also check for
	__start_SECNAME and __stop_SECNAME symbols.
	* elf64-x86-64.c (elf_x86_64_convert_load_reloc): Likewise.
	* elflink.c (_bfd_elf_is_start_stop): Removed.
	(_bfd_elf_gc_mark_rsec): Check start_stop instead of calling
	_bfd_elf_is_start_stop.
	(elf_gc_propagate_vtable_entries_used): Skip __start_SECNAME and
	__stop_SECNAME symbols.  Updated.
	(elf_gc_smash_unused_vtentry_relocs): Likewise.
	(bfd_elf_gc_record_vtinherit): Likewise.
	(bfd_elf_gc_record_vtentry): Likewise.

ld/

	PR ld/20022
	PR ld/21557
	PR ld/21562
	PR ld/21571
	* ld.texinfo: Update __start_SECNAME/__stop_SECNAME symbols.
	* ldlang.c (lang_insert_orphan): Move handling of __start_SECNAME
	and __stop_SECNAME symbols to ...
	(lang_set_startof): Here.  Also define __start_SECNAME and
	__stop_SECNAME for -Ur.
	* emultempl/elf32.em (gld${EMULATION_NAME}_after_open): Mark
	referenced __start_SECNAME and __stop_SECNAME symbols as hidden
	and set start_stop for garbage collection.
	* testsuite/ld-elf/pr21562a.d: New file.
	* testsuite/ld-elf/pr21562a.s: Likewise.
	* testsuite/ld-elf/pr21562a.t: Likewise.
	* testsuite/ld-elf/pr21562b.d: Likewise.
	* testsuite/ld-elf/pr21562b.s: Likewise.
	* testsuite/ld-elf/pr21562b.t: Likewise.
	* testsuite/ld-elf/pr21562c.d: Likewise.
	* testsuite/ld-elf/pr21562c.t: Likewise.
	* testsuite/ld-elf/pr21562d.d: Likewise.
	* testsuite/ld-elf/pr21562d.t: Likewise.
	* testsuite/ld-elf/pr21562e.d: Likewise.
	* testsuite/ld-elf/pr21562f.d: Likewise.
	* testsuite/ld-elf/pr21562g.d: Likewise.
	* testsuite/ld-elf/pr21562h.d: Likewise.
	* testsuite/ld-elf/pr21562i.d: Likewise.
	* testsuite/ld-elf/pr21562j.d: Likewise.
	* testsuite/ld-elf/pr21562k.d: Likewise.
	* testsuite/ld-elf/pr21562l.d: Likewise.
	* testsuite/ld-elf/pr21562m.d: Likewise.
	* testsuite/ld-elf/pr21562n.d: Likewise.
	* testsuite/ld-gc/pr20022.d: Likewise.
	* testsuite/ld-gc/pr20022a.s: Likewise.
	* testsuite/ld-gc/pr20022b.s: Likewise.
	* testsuite/ld-gc/gc.exp: Run PR ld/20022 tests.
	* testsuite/ld-gc/pr19161.d: Also accept local __start_SECNAME
	symbol.
	* testsuite/ld-gc/start.d: Likewise.
	* testsuite/ld-x86-64/lea1a.d: Updated.
	* testsuite/ld-x86-64/lea1b.d: Updated.
	* testsuite/ld-x86-64/lea1d.d: Updated.
	* testsuite/ld-x86-64/lea1e.d: Likewise.
---
 bfd/ChangeLog                  |  21 ++++++
 bfd/elf-bfd.h                  |  16 +++--
 bfd/elf32-i386.c               |  12 ++--
 bfd/elf64-x86-64.c             |  28 ++++----
 bfd/elflink.c                  | 118 ++++++++++-----------------------
 ld/ChangeLog                   |  46 +++++++++++++
 ld/emultempl/elf32.em          |  64 ++++++++++++++++--
 ld/ld.texinfo                  |  16 ++---
 ld/ldlang.c                    | 115 +++++++++++++++-----------------
 ld/testsuite/ld-elf/pr21562a.d |   9 +++
 ld/testsuite/ld-elf/pr21562a.s |   8 +++
 ld/testsuite/ld-elf/pr21562a.t |   3 +
 ld/testsuite/ld-elf/pr21562b.d |   9 +++
 ld/testsuite/ld-elf/pr21562b.s |   8 +++
 ld/testsuite/ld-elf/pr21562b.t |   5 ++
 ld/testsuite/ld-elf/pr21562c.d |  10 +++
 ld/testsuite/ld-elf/pr21562c.t |   7 ++
 ld/testsuite/ld-elf/pr21562d.d |  10 +++
 ld/testsuite/ld-elf/pr21562d.t |   5 ++
 ld/testsuite/ld-elf/pr21562e.d |  10 +++
 ld/testsuite/ld-elf/pr21562f.d |  10 +++
 ld/testsuite/ld-elf/pr21562g.d |  10 +++
 ld/testsuite/ld-elf/pr21562h.d |  10 +++
 ld/testsuite/ld-elf/pr21562i.d |  10 +++
 ld/testsuite/ld-elf/pr21562j.d |  10 +++
 ld/testsuite/ld-elf/pr21562k.d |  10 +++
 ld/testsuite/ld-elf/pr21562l.d |  10 +++
 ld/testsuite/ld-elf/pr21562m.d |  10 +++
 ld/testsuite/ld-elf/pr21562n.d |  10 +++
 ld/testsuite/ld-gc/gc.exp      |   6 ++
 ld/testsuite/ld-gc/pr19161.d   |   2 +-
 ld/testsuite/ld-gc/pr20022.d   |  11 +++
 ld/testsuite/ld-gc/pr20022a.s  |   8 +++
 ld/testsuite/ld-gc/pr20022b.s  |   8 +++
 ld/testsuite/ld-gc/start.d     |   2 +-
 ld/testsuite/ld-x86-64/lea1a.d |   2 +-
 ld/testsuite/ld-x86-64/lea1b.d |   2 +-
 ld/testsuite/ld-x86-64/lea1d.d |   2 +-
 ld/testsuite/ld-x86-64/lea1e.d |   2 +-
 39 files changed, 473 insertions(+), 182 deletions(-)
 create mode 100644 ld/testsuite/ld-elf/pr21562a.d
 create mode 100644 ld/testsuite/ld-elf/pr21562a.s
 create mode 100644 ld/testsuite/ld-elf/pr21562a.t
 create mode 100644 ld/testsuite/ld-elf/pr21562b.d
 create mode 100644 ld/testsuite/ld-elf/pr21562b.s
 create mode 100644 ld/testsuite/ld-elf/pr21562b.t
 create mode 100644 ld/testsuite/ld-elf/pr21562c.d
 create mode 100644 ld/testsuite/ld-elf/pr21562c.t
 create mode 100644 ld/testsuite/ld-elf/pr21562d.d
 create mode 100644 ld/testsuite/ld-elf/pr21562d.t
 create mode 100644 ld/testsuite/ld-elf/pr21562e.d
 create mode 100644 ld/testsuite/ld-elf/pr21562f.d
 create mode 100644 ld/testsuite/ld-elf/pr21562g.d
 create mode 100644 ld/testsuite/ld-elf/pr21562h.d
 create mode 100644 ld/testsuite/ld-elf/pr21562i.d
 create mode 100644 ld/testsuite/ld-elf/pr21562j.d
 create mode 100644 ld/testsuite/ld-elf/pr21562k.d
 create mode 100644 ld/testsuite/ld-elf/pr21562l.d
 create mode 100644 ld/testsuite/ld-elf/pr21562m.d
 create mode 100644 ld/testsuite/ld-elf/pr21562n.d
 create mode 100644 ld/testsuite/ld-gc/pr20022.d
 create mode 100644 ld/testsuite/ld-gc/pr20022a.s
 create mode 100644 ld/testsuite/ld-gc/pr20022b.s

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index acddb3a2eec..edff887d20e 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,24 @@
+2017-06-13  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR ld/20022
+	PR ld/21557
+	PR ld/21562
+	PR ld/21571
+	* elf-bfd.h (elf_link_hash_entry): Add start_stop.  Change the
+	vtable field to a union.
+	(_bfd_elf_is_start_stop): Removed.
+	* elf32-i386.c (elf_i386_convert_load_reloc): Also check for
+	__start_SECNAME and __stop_SECNAME symbols.
+	* elf64-x86-64.c (elf_x86_64_convert_load_reloc): Likewise.
+	* elflink.c (_bfd_elf_is_start_stop): Removed.
+	(_bfd_elf_gc_mark_rsec): Check start_stop instead of calling
+	_bfd_elf_is_start_stop.
+	(elf_gc_propagate_vtable_entries_used): Skip __start_SECNAME and
+	__stop_SECNAME symbols.  Updated.
+	(elf_gc_smash_unused_vtentry_relocs): Likewise.
+	(bfd_elf_gc_record_vtinherit): Likewise.
+	(bfd_elf_gc_record_vtentry): Likewise.
+
 2017-06-13  Nick Clifton  <nickc@redhat.com>
 
 	PR ld/21524
diff --git a/bfd/elf-bfd.h b/bfd/elf-bfd.h
index 567b63a2de7..fe15b93342a 100644
--- a/bfd/elf-bfd.h
+++ b/bfd/elf-bfd.h
@@ -213,6 +213,9 @@ struct elf_link_hash_entry
   /* Symbol is defined by a shared library with non-default visibility
      in a read/write section.  */
   unsigned int protected_def : 1;
+  /* Symbol is __start_SECNAME or __stop_SECNAME to mark section
+     SECNAME.  */
+  unsigned int start_stop : 1;
 
   /* String table index in .dynstr if this is a dynamic symbol.  */
   unsigned long dynstr_index;
@@ -243,7 +246,15 @@ struct elf_link_hash_entry
     struct bfd_elf_version_tree *vertree;
   } verinfo;
 
-  struct elf_link_virtual_table_entry *vtable;
+  union
+  {
+    /* For __start_SECNAME and __stop_SECNAME symbols, record the first
+       input section whose section name is SECNAME.  */
+    asection *start_stop_section;
+
+    /* Vtable information. */
+    struct elf_link_virtual_table_entry *vtable;
+  } u2;
 };
 
 /* Will references to this symbol always reference the symbol
@@ -2445,9 +2456,6 @@ extern bfd_boolean bfd_elf_gc_common_finalize_got_offsets
 extern bfd_boolean bfd_elf_gc_common_final_link
   (bfd *, struct bfd_link_info *);
 
-extern asection *_bfd_elf_is_start_stop
-  (const struct bfd_link_info *, struct elf_link_hash_entry *);
-
 extern bfd_boolean bfd_elf_reloc_symbol_deleted_p
   (bfd_vma, void *);
 
diff --git a/bfd/elf32-i386.c b/bfd/elf32-i386.c
index f9142a98d5f..6636551fb01 100644
--- a/bfd/elf32-i386.c
+++ b/bfd/elf32-i386.c
@@ -1787,11 +1787,13 @@ convert_branch:
 	return TRUE;
 
       /* def_regular is set by an assignment in a linker script in
-	 bfd_elf_record_link_assignment.  */
-      if ((h->def_regular
-	   || h->root.type == bfd_link_hash_defined
-	   || h->root.type == bfd_link_hash_defweak)
-	  && SYMBOL_REFERENCES_LOCAL (link_info, h))
+	 bfd_elf_record_link_assignment.  start_stop is set on
+	 __start_SECNAME/__stop_SECNAME which mark section SECNAME.  */
+      if (h->start_stop
+	  || ((h->def_regular
+	       || h->root.type == bfd_link_hash_defined
+	       || h->root.type == bfd_link_hash_defweak)
+	      && SYMBOL_REFERENCES_LOCAL (link_info, h)))
 	{
 convert_load:
 	  if (opcode == 0x8b)
diff --git a/bfd/elf64-x86-64.c b/bfd/elf64-x86-64.c
index 53060197fe6..ab6f06887e0 100644
--- a/bfd/elf64-x86-64.c
+++ b/bfd/elf64-x86-64.c
@@ -1920,21 +1920,25 @@ elf_x86_64_convert_load_reloc (bfd *abfd, asection *sec,
 	}
       /* Avoid optimizing GOTPCREL relocations againt _DYNAMIC since
 	 ld.so may use its link-time address.  */
-      else if ((h->def_regular
-		|| h->root.type == bfd_link_hash_defined
-		|| h->root.type == bfd_link_hash_defweak)
-	       && h != htab->elf.hdynamic
-	       && SYMBOL_REFERENCES_LOCAL (link_info, h))
+      else if (h->start_stop
+	       || ((h->def_regular
+		    || h->root.type == bfd_link_hash_defined
+		    || h->root.type == bfd_link_hash_defweak)
+		   && h != htab->elf.hdynamic
+		   && SYMBOL_REFERENCES_LOCAL (link_info, h)))
 	{
 	  /* bfd_link_hash_new or bfd_link_hash_undefined is
 	     set by an assignment in a linker script in
-	     bfd_elf_record_link_assignment.   */
-	  if (h->def_regular
-	      && (h->root.type == bfd_link_hash_new
-		  || h->root.type == bfd_link_hash_undefined
-		  || ((h->root.type == bfd_link_hash_defined
-		       || h->root.type == bfd_link_hash_defweak)
-		      && h->root.u.def.section == bfd_und_section_ptr)))
+	     bfd_elf_record_link_assignment.  start_stop is set
+	     on __start_SECNAME/__stop_SECNAME which mark section
+	     SECNAME.  */
+	  if (h->start_stop
+	      || (h->def_regular
+		  && (h->root.type == bfd_link_hash_new
+		      || h->root.type == bfd_link_hash_undefined
+		      || ((h->root.type == bfd_link_hash_defined
+			   || h->root.type == bfd_link_hash_defweak)
+			  && h->root.u.def.section == bfd_und_section_ptr))))
 	    {
 	      /* Skip since R_X86_64_32/R_X86_64_32S may overflow.  */
 	      if (require_reloc_pc32)
diff --git a/bfd/elflink.c b/bfd/elflink.c
index f0ca33f155b..9b0f5443520 100644
--- a/bfd/elflink.c
+++ b/bfd/elflink.c
@@ -12698,55 +12698,6 @@ elf_gc_mark_debug_section (asection *sec ATTRIBUTE_UNUSED,
   return NULL;
 }
 
-/* For undefined __start_<name> and __stop_<name> symbols, return the
-   first input section matching <name>.  Return NULL otherwise.  */
-
-asection *
-_bfd_elf_is_start_stop (const struct bfd_link_info *info,
-			struct elf_link_hash_entry *h)
-{
-  asection *s;
-  const char *sec_name;
-
-  if (h->root.type != bfd_link_hash_undefined
-      && h->root.type != bfd_link_hash_undefweak)
-    return NULL;
-
-  s = h->root.u.undef.section;
-  if (s != NULL)
-    {
-      if (s == (asection *) 0 - 1)
-	return NULL;
-      return s;
-    }
-
-  sec_name = NULL;
-  if (strncmp (h->root.root.string, "__start_", 8) == 0)
-    sec_name = h->root.root.string + 8;
-  else if (strncmp (h->root.root.string, "__stop_", 7) == 0)
-    sec_name = h->root.root.string + 7;
-
-  if (sec_name != NULL && *sec_name != '\0')
-    {
-      bfd *i;
-
-      for (i = info->input_bfds; i != NULL; i = i->link.next)
-	{
-	  s = bfd_get_section_by_name (i, sec_name);
-	  if (s != NULL)
-	    {
-	      h->root.u.undef.section = s;
-	      break;
-	    }
-	}
-    }
-
-  if (s == NULL)
-    h->root.u.undef.section = (asection *) 0 - 1;
-
-  return s;
-}
-
 /* COOKIE->rel describes a relocation against section SEC, which is
    a section we've decided to keep.  Return the section that contains
    the relocation symbol, or NULL if no section contains it.  */
@@ -12792,10 +12743,9 @@ _bfd_elf_gc_mark_rsec (struct bfd_link_info *info, asection *sec,
 	     or __stop_XXX symbols.  The linker will later define such
 	     symbols for orphan input sections that have a name
 	     representable as a C identifier.  */
-	  asection *s = _bfd_elf_is_start_stop (info, h);
-
-	  if (s != NULL)
+	  if (h->start_stop)
 	    {
+	      asection *s = h->u2.start_stop_section;
 	      *start_stop = !s->gc_mark;
 	      return s;
 	    }
@@ -13136,26 +13086,28 @@ static bfd_boolean
 elf_gc_propagate_vtable_entries_used (struct elf_link_hash_entry *h, void *okp)
 {
   /* Those that are not vtables.  */
-  if (h->vtable == NULL || h->vtable->parent == NULL)
+  if (h->start_stop
+      || h->u2.vtable == NULL
+      || h->u2.vtable->parent == NULL)
     return TRUE;
 
   /* Those vtables that do not have parents, we cannot merge.  */
-  if (h->vtable->parent == (struct elf_link_hash_entry *) -1)
+  if (h->u2.vtable->parent == (struct elf_link_hash_entry *) -1)
     return TRUE;
 
   /* If we've already been done, exit.  */
-  if (h->vtable->used && h->vtable->used[-1])
+  if (h->u2.vtable->used && h->u2.vtable->used[-1])
     return TRUE;
 
   /* Make sure the parent's table is up to date.  */
-  elf_gc_propagate_vtable_entries_used (h->vtable->parent, okp);
+  elf_gc_propagate_vtable_entries_used (h->u2.vtable->parent, okp);
 
-  if (h->vtable->used == NULL)
+  if (h->u2.vtable->used == NULL)
     {
       /* None of this table's entries were referenced.  Re-use the
 	 parent's table.  */
-      h->vtable->used = h->vtable->parent->vtable->used;
-      h->vtable->size = h->vtable->parent->vtable->size;
+      h->u2.vtable->used = h->u2.vtable->parent->u2.vtable->used;
+      h->u2.vtable->size = h->u2.vtable->parent->u2.vtable->size;
     }
   else
     {
@@ -13163,9 +13115,9 @@ elf_gc_propagate_vtable_entries_used (struct elf_link_hash_entry *h, void *okp)
       bfd_boolean *cu, *pu;
 
       /* Or the parent's entries into ours.  */
-      cu = h->vtable->used;
+      cu = h->u2.vtable->used;
       cu[-1] = TRUE;
-      pu = h->vtable->parent->vtable->used;
+      pu = h->u2.vtable->parent->u2.vtable->used;
       if (pu != NULL)
 	{
 	  const struct elf_backend_data *bed;
@@ -13173,7 +13125,7 @@ elf_gc_propagate_vtable_entries_used (struct elf_link_hash_entry *h, void *okp)
 
 	  bed = get_elf_backend_data (h->root.u.def.section->owner);
 	  log_file_align = bed->s->log_file_align;
-	  n = h->vtable->parent->vtable->size >> log_file_align;
+	  n = h->u2.vtable->parent->u2.vtable->size >> log_file_align;
 	  while (n--)
 	    {
 	      if (*pu)
@@ -13198,7 +13150,9 @@ elf_gc_smash_unused_vtentry_relocs (struct elf_link_hash_entry *h, void *okp)
 
   /* Take care of both those symbols that do not describe vtables as
      well as those that are not loaded.  */
-  if (h->vtable == NULL || h->vtable->parent == NULL)
+  if (h->start_stop
+      || h->u2.vtable == NULL
+      || h->u2.vtable->parent == NULL)
     return TRUE;
 
   BFD_ASSERT (h->root.type == bfd_link_hash_defined
@@ -13220,11 +13174,11 @@ elf_gc_smash_unused_vtentry_relocs (struct elf_link_hash_entry *h, void *okp)
     if (rel->r_offset >= hstart && rel->r_offset < hend)
       {
 	/* If the entry is in use, do nothing.  */
-	if (h->vtable->used
-	    && (rel->r_offset - hstart) < h->vtable->size)
+	if (h->u2.vtable->used
+	    && (rel->r_offset - hstart) < h->u2.vtable->size)
 	  {
 	    bfd_vma entry = (rel->r_offset - hstart) >> log_file_align;
-	    if (h->vtable->used[entry])
+	    if (h->u2.vtable->used[entry])
 	      continue;
 	  }
 	/* Otherwise, kill it.  */
@@ -13448,11 +13402,11 @@ bfd_elf_gc_record_vtinherit (bfd *abfd,
   return FALSE;
 
  win:
-  if (!child->vtable)
+  if (!child->u2.vtable)
     {
-      child->vtable = ((struct elf_link_virtual_table_entry *)
-		       bfd_zalloc (abfd, sizeof (*child->vtable)));
-      if (!child->vtable)
+      child->u2.vtable = ((struct elf_link_virtual_table_entry *)
+			  bfd_zalloc (abfd, sizeof (*child->u2.vtable)));
+      if (!child->u2.vtable)
 	return FALSE;
     }
   if (!h)
@@ -13462,10 +13416,10 @@ bfd_elf_gc_record_vtinherit (bfd *abfd,
 	 would be bad.  It isn't worth paging in the local symbols to be
 	 sure though; that case should simply be handled by the assembler.  */
 
-      child->vtable->parent = (struct elf_link_hash_entry *) -1;
+      child->u2.vtable->parent = (struct elf_link_hash_entry *) -1;
     }
   else
-    child->vtable->parent = h;
+    child->u2.vtable->parent = h;
 
   return TRUE;
 }
@@ -13481,18 +13435,18 @@ bfd_elf_gc_record_vtentry (bfd *abfd ATTRIBUTE_UNUSED,
   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
   unsigned int log_file_align = bed->s->log_file_align;
 
-  if (!h->vtable)
+  if (!h->u2.vtable)
     {
-      h->vtable = ((struct elf_link_virtual_table_entry *)
-		   bfd_zalloc (abfd, sizeof (*h->vtable)));
-      if (!h->vtable)
+      h->u2.vtable = ((struct elf_link_virtual_table_entry *)
+		      bfd_zalloc (abfd, sizeof (*h->u2.vtable)));
+      if (!h->u2.vtable)
 	return FALSE;
     }
 
-  if (addend >= h->vtable->size)
+  if (addend >= h->u2.vtable->size)
     {
       size_t size, bytes, file_align;
-      bfd_boolean *ptr = h->vtable->used;
+      bfd_boolean *ptr = h->u2.vtable->used;
 
       /* While the symbol is undefined, we have to be prepared to handle
 	 a zero size.  */
@@ -13523,7 +13477,7 @@ bfd_elf_gc_record_vtentry (bfd *abfd ATTRIBUTE_UNUSED,
 	    {
 	      size_t oldbytes;
 
-	      oldbytes = (((h->vtable->size >> log_file_align) + 1)
+	      oldbytes = (((h->u2.vtable->size >> log_file_align) + 1)
 			  * sizeof (bfd_boolean));
 	      memset (((char *) ptr) + oldbytes, 0, bytes - oldbytes);
 	    }
@@ -13535,11 +13489,11 @@ bfd_elf_gc_record_vtentry (bfd *abfd ATTRIBUTE_UNUSED,
 	return FALSE;
 
       /* And arrange for that done flag to be at index -1.  */
-      h->vtable->used = ptr + 1;
-      h->vtable->size = size;
+      h->u2.vtable->used = ptr + 1;
+      h->u2.vtable->size = size;
     }
 
-  h->vtable->used[addend >> log_file_align] = TRUE;
+  h->u2.vtable->used[addend >> log_file_align] = TRUE;
 
   return TRUE;
 }
diff --git a/ld/ChangeLog b/ld/ChangeLog
index 309bb3a49f1..dcfc6022630 100644
--- a/ld/ChangeLog
+++ b/ld/ChangeLog
@@ -1,3 +1,49 @@
+2017-06-13  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR ld/20022
+	PR ld/21557
+	PR ld/21562
+	PR ld/21571
+	* ld.texinfo: Update __start_SECNAME/__stop_SECNAME symbols.
+	* ldlang.c (lang_insert_orphan): Move handling of __start_SECNAME
+	and __stop_SECNAME symbols to ...
+	(lang_set_startof): Here.  Also define __start_SECNAME and
+	__stop_SECNAME for -Ur.
+	* emultempl/elf32.em (gld${EMULATION_NAME}_after_open): Mark
+	referenced __start_SECNAME and __stop_SECNAME symbols as hidden
+	and set start_stop for garbage collection.
+	* testsuite/ld-elf/pr21562a.d: New file.
+	* testsuite/ld-elf/pr21562a.s: Likewise.
+	* testsuite/ld-elf/pr21562a.t: Likewise.
+	* testsuite/ld-elf/pr21562b.d: Likewise.
+	* testsuite/ld-elf/pr21562b.s: Likewise.
+	* testsuite/ld-elf/pr21562b.t: Likewise.
+	* testsuite/ld-elf/pr21562c.d: Likewise.
+	* testsuite/ld-elf/pr21562c.t: Likewise.
+	* testsuite/ld-elf/pr21562d.d: Likewise.
+	* testsuite/ld-elf/pr21562d.t: Likewise.
+	* testsuite/ld-elf/pr21562e.d: Likewise.
+	* testsuite/ld-elf/pr21562f.d: Likewise.
+	* testsuite/ld-elf/pr21562g.d: Likewise.
+	* testsuite/ld-elf/pr21562h.d: Likewise.
+	* testsuite/ld-elf/pr21562i.d: Likewise.
+	* testsuite/ld-elf/pr21562j.d: Likewise.
+	* testsuite/ld-elf/pr21562k.d: Likewise.
+	* testsuite/ld-elf/pr21562l.d: Likewise.
+	* testsuite/ld-elf/pr21562m.d: Likewise.
+	* testsuite/ld-elf/pr21562n.d: Likewise.
+	* testsuite/ld-gc/pr20022.d: Likewise.
+	* testsuite/ld-gc/pr20022a.s: Likewise.
+	* testsuite/ld-gc/pr20022b.s: Likewise.
+	* testsuite/ld-gc/gc.exp: Run PR ld/20022 tests.
+	* testsuite/ld-gc/pr19161.d: Also accept local __start_SECNAME
+	symbol.
+	* testsuite/ld-gc/start.d: Likewise.
+	* testsuite/ld-x86-64/lea1a.d: Updated.
+	* testsuite/ld-x86-64/lea1b.d: Updated.
+	* testsuite/ld-x86-64/lea1d.d: Updated.
+	* testsuite/ld-x86-64/lea1e.d: Likewise.
+
 2017-06-13  H.J. Lu  <hongjiu.lu@intel.com>
 
 	* testsuite/ld-elf/sizeof.d: New file.
diff --git a/ld/emultempl/elf32.em b/ld/emultempl/elf32.em
index 0260b7ac44c..9468f7d29f2 100644
--- a/ld/emultempl/elf32.em
+++ b/ld/emultempl/elf32.em
@@ -1216,6 +1216,9 @@ gld${EMULATION_NAME}_after_open (void)
 {
   struct bfd_link_needed_list *needed, *l;
   struct elf_link_hash_table *htab;
+  asection *s;
+  bfd *abfd;
+  char leading_char;
 
   after_open_default ();
 
@@ -1239,8 +1242,6 @@ gld${EMULATION_NAME}_after_open (void)
 
   if (emit_note_gnu_build_id != NULL)
     {
-      bfd *abfd;
-
       /* Find an ELF input.  */
       for (abfd = link_info.input_bfds;
 	   abfd != (bfd *) NULL; abfd = abfd->link.next)
@@ -1276,11 +1277,66 @@ gld${EMULATION_NAME}_after_open (void)
       return;
     }
 
+  leading_char = bfd_get_symbol_leading_char (link_info.output_bfd);
+
+  /* Check for input sections whose names match references to
+     __start_SECNAME or __stop_SECNAME symbols.  Mark the matched
+     symbols as hidden and set start_stop for garbage collection.  */
+  for (abfd = link_info.input_bfds; abfd; abfd = abfd->link.next)
+    for (s = abfd->sections; s; s = s->next)
+      {
+	const char *name = bfd_get_section_name (abfd, s);
+	const char *ps;
+
+	for (ps = name; *ps != '\0'; ps++)
+	  if (!ISALNUM ((unsigned char) *ps) && *ps != '_')
+	    break;
+	if (*ps == '\0')
+	  {
+	    struct elf_link_hash_entry *h;
+	    char *symbol = (char *) xmalloc (ps - name
+					     + sizeof "__start_" + 1);
+
+	    symbol[0] = leading_char;
+	    sprintf (symbol + (leading_char != 0), "__start_%s", name);
+	    h = elf_link_hash_lookup (elf_hash_table (&link_info),
+				      symbol, FALSE, FALSE, TRUE);
+	    if (h != NULL
+		&& (h->root.type == bfd_link_hash_undefined
+		    || h->root.type == bfd_link_hash_undefweak)
+		&& h->u2.start_stop_section == NULL)
+	      {
+		h->start_stop = 1;
+		h->u2.start_stop_section = s;
+		_bfd_elf_link_hash_hide_symbol (&link_info, h, TRUE);
+		if (ELF_ST_VISIBILITY (h->other) != STV_INTERNAL)
+		  h->other = ((h->other & ~ELF_ST_VISIBILITY (-1))
+			      | STV_HIDDEN);
+	      }
+
+	    symbol[0] = leading_char;
+	    sprintf (symbol + (leading_char != 0), "__stop_%s", name);
+	    h = elf_link_hash_lookup (elf_hash_table (&link_info),
+				      symbol, FALSE, FALSE, TRUE);
+	    if (h != NULL
+		&& (h->root.type == bfd_link_hash_undefined
+		    || h->root.type == bfd_link_hash_undefweak)
+		&& h->u2.start_stop_section == NULL)
+	      {
+		h->start_stop = 1;
+		h->u2.start_stop_section = s;
+		_bfd_elf_link_hash_hide_symbol (&link_info, h, TRUE);
+		if (ELF_ST_VISIBILITY (h->other) != STV_INTERNAL)
+		  h->other = ((h->other & ~ELF_ST_VISIBILITY (-1))
+			      | STV_HIDDEN);
+	      }
+	  }
+      }
+
   if (!link_info.traditional_format)
     {
-      bfd *abfd, *elfbfd = NULL;
+      bfd *elfbfd = NULL;
       bfd_boolean warn_eh_frame = FALSE;
-      asection *s;
       int seen_type = 0;
 
       for (abfd = link_info.input_bfds; abfd; abfd = abfd->link.next)
diff --git a/ld/ld.texinfo b/ld/ld.texinfo
index 790b52f0251..44ad84b3517 100644
--- a/ld/ld.texinfo
+++ b/ld/ld.texinfo
@@ -4657,6 +4657,14 @@ SECTIONS @{
 @end group
 @end smallexample
 
+If an output section's name is the same as the input section's name
+and is representable as a C identifier, then the linker will
+automatically @pxref{PROVIDE} two symbols: __start_SECNAME and
+__stop_SECNAME, where SECNAME is the name of the section.  These
+indicate the start address and end address of the output section
+respectively.  Note: most section names are not representable as
+C identifiers because they contain a @samp{.} character.
+
 @node Output Section Data
 @subsection Output Section Data
 @cindex data
@@ -5841,14 +5849,6 @@ The command line options @samp{--orphan-handling} and @samp{--unique}
 (@pxref{Options,,Command Line Options}) can be used to control which
 output sections an orphan is placed in.
 
-If an orphaned section's name is representable as a C identifier then
-the linker will automatically @pxref{PROVIDE} two symbols:
-__start_SECNAME and __stop_SECNAME, where SECNAME is the name of the
-section.  These indicate the start address and end address of the
-orphaned section respectively.  Note: most section names are not
-representable as C identifiers because they contain a @samp{.}
-character.
-
 @node Location Counter
 @subsection The Location Counter
 @kindex .
diff --git a/ld/ldlang.c b/ld/ldlang.c
index 252400bd510..f8e4f528799 100644
--- a/ld/ldlang.c
+++ b/ld/ldlang.c
@@ -1829,8 +1829,6 @@ lang_insert_orphan (asection *s,
 		    lang_statement_list_type *add_child)
 {
   lang_statement_list_type add;
-  const char *ps;
-  lang_assignment_statement_type *start_assign;
   lang_output_section_statement_type *os;
   lang_output_section_statement_type **os_tail;
 
@@ -1852,29 +1850,6 @@ lang_insert_orphan (asection *s,
   os = lang_enter_output_section_statement (secname, address, normal_section,
 					    NULL, NULL, NULL, constraint, 0);
 
-  ps = NULL;
-  start_assign = NULL;
-  if (config.build_constructors && *os_tail == os)
-    {
-      /* If the name of the section is representable in C, then create
-	 symbols to mark the start and the end of the section.  */
-      for (ps = secname; *ps != '\0'; ps++)
-	if (!ISALNUM ((unsigned char) *ps) && *ps != '_')
-	  break;
-      if (*ps == '\0')
-	{
-	  char *symname;
-
-	  symname = (char *) xmalloc (ps - secname + sizeof "__start_" + 1);
-	  symname[0] = bfd_get_symbol_leading_char (link_info.output_bfd);
-	  sprintf (symname + (symname[0] != 0), "__start_%s", secname);
-	  start_assign
-	    = lang_add_assignment (exp_provide (symname,
-						exp_nameop (NAME, "."),
-						FALSE));
-	}
-    }
-
   if (add_child == NULL)
     add_child = &os->children;
   lang_add_section (add_child, s, NULL, os);
@@ -1894,27 +1869,6 @@ lang_insert_orphan (asection *s,
     lang_leave_output_section_statement (NULL, DEFAULT_MEMORY_REGION, NULL,
 					 NULL);
 
-  if (start_assign != NULL)
-    {
-      char *symname;
-      lang_assignment_statement_type *stop_assign;
-      bfd_vma dot;
-
-      symname = (char *) xmalloc (ps - secname + sizeof "__stop_" + 1);
-      symname[0] = bfd_get_symbol_leading_char (link_info.output_bfd);
-      sprintf (symname + (symname[0] != 0), "__stop_%s", secname);
-      stop_assign
-	= lang_add_assignment (exp_provide (symname,
-					    exp_nameop (NAME, "."),
-					    FALSE));
-      /* Evaluate the expression to define the symbol if referenced,
-	 before sizing dynamic sections.  */
-      dot = os->bfd_section->vma;
-      exp_fold_tree (start_assign->exp, os->bfd_section, &dot);
-      dot += TO_ADDR (s->size);
-      exp_fold_tree (stop_assign->exp, os->bfd_section, &dot);
-    }
-
   /* Restore the global list pointer.  */
   if (after != NULL)
     pop_stat_ptr ();
@@ -5924,20 +5878,25 @@ section_for_dot (void)
   return bfd_abs_section_ptr;
 }
 
-/* Fix any .startof. or .sizeof. symbols.  When the assemblers see the
-   operator .startof. (section_name), it produces an undefined symbol
-   .startof.section_name.  Similarly, when it sees
+/* Fix any .startof., .sizeof., __start or __stop symbols.  When the
+   assemblers see the operator .startof. (section_name), it produces
+   an undefined symbol .startof.section_name.  Similarly, when it sees
    .sizeof. (section_name), it produces an undefined symbol
-   .sizeof.section_name.  For all the output sections, we look for
-   such symbols, and set them to the correct value.  */
+   .sizeof.section_name.  Also for ELF linker, __start_XXX or __stop_XXX
+   symbols should be resolved to the start and end of section XXX.  For
+   all the output sections, we look for such symbols, and set them to
+   the correct value.  */
 
 static void
 lang_set_startof (void)
 {
   asection *s;
+  char leading_char;
+  bfd_boolean is_elf = (bfd_get_flavour (link_info.output_bfd)
+			== bfd_target_elf_flavour);
+  bfd_boolean is_elocatable = bfd_link_relocatable (&link_info);
 
-  if (bfd_link_relocatable (&link_info))
-    return;
+  leading_char = bfd_get_symbol_leading_char (link_info.output_bfd);
 
   for (s = link_info.output_bfd->sections; s != NULL; s = s->next)
     {
@@ -5948,24 +5907,58 @@ lang_set_startof (void)
       secname = bfd_get_section_name (link_info.output_bfd, s);
       buf = (char *) xmalloc (10 + strlen (secname));
 
-      sprintf (buf, ".startof.%s", secname);
-      h = bfd_link_hash_lookup (link_info.hash, buf, FALSE, FALSE, TRUE);
-      if (h != NULL && h->type == bfd_link_hash_undefined)
+      if (!is_elocatable)
+	{
+	  sprintf (buf, ".startof.%s", secname);
+	  h = bfd_link_hash_lookup (link_info.hash, buf, FALSE, FALSE,
+				    TRUE);
+	  if (h != NULL && h->type == bfd_link_hash_undefined)
+	    {
+	      h->type = bfd_link_hash_defined;
+	      h->u.def.value = 0;
+	      h->u.def.section = s;
+	    }
+
+	  sprintf (buf, ".sizeof.%s", secname);
+	  h = bfd_link_hash_lookup (link_info.hash, buf, FALSE, FALSE,
+				    TRUE);
+	  if (h != NULL && h->type == bfd_link_hash_undefined)
+	    {
+	      h->type = bfd_link_hash_defined;
+	      h->u.def.value = TO_ADDR (s->size);
+	      h->u.def.section = bfd_abs_section_ptr;
+	    }
+	}
+
+      buf[0] = leading_char;
+      sprintf (buf + (buf[0] != 0), "__start_%s", secname);
+      h = bfd_link_hash_lookup (link_info.hash, buf, FALSE, FALSE,
+				TRUE);
+      if (h != NULL
+	  && (h->type == bfd_link_hash_undefined
+	      || h->type == bfd_link_hash_undefweak))
 	{
 	  h->type = bfd_link_hash_defined;
 	  h->u.def.value = 0;
 	  h->u.def.section = s;
+	  if (is_elf)
+	    ((struct elf_link_hash_entry *) h)->def_regular = 1;
 	}
 
-      sprintf (buf, ".sizeof.%s", secname);
-      h = bfd_link_hash_lookup (link_info.hash, buf, FALSE, FALSE, TRUE);
-      if (h != NULL && h->type == bfd_link_hash_undefined)
+      buf[0] = leading_char;
+      sprintf (buf + (buf[0] != 0), "__stop_%s", secname);
+      h = bfd_link_hash_lookup (link_info.hash, buf, FALSE, FALSE,
+				TRUE);
+      if (h != NULL
+	  && (h->type == bfd_link_hash_undefined
+	      || h->type == bfd_link_hash_undefweak))
 	{
 	  h->type = bfd_link_hash_defined;
 	  h->u.def.value = TO_ADDR (s->size);
-	  h->u.def.section = bfd_abs_section_ptr;
+	  h->u.def.section = s;
+	  if (is_elf)
+	    ((struct elf_link_hash_entry *) h)->def_regular = 1;
 	}
-
       free (buf);
     }
 }
diff --git a/ld/testsuite/ld-elf/pr21562a.d b/ld/testsuite/ld-elf/pr21562a.d
new file mode 100644
index 00000000000..009dcfc05c3
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr21562a.d
@@ -0,0 +1,9 @@
+#ld: -shared -z defs --gc-sections
+#readelf: -s -S --wide
+#target: *-*-linux* *-*-gnu*
+
+#...
+  \[[ 0-9]+\] scnfoo[ \t]+PROGBITS[ \t]+[0-9a-f]+ +[0-9a-f]+ +0*10[ \t]+.*
+#...
+ +[0-9]+: +[0-9a-f]+ +[0-9a-f]+ +NOTYPE +LOCAL +DEFAULT +[0-9]+ +__start_scnfoo
+#pass
diff --git a/ld/testsuite/ld-elf/pr21562a.s b/ld/testsuite/ld-elf/pr21562a.s
new file mode 100644
index 00000000000..ec36da4b8e5
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr21562a.s
@@ -0,0 +1,8 @@
+        .section        scnfoo,"aw",%progbits
+        .zero 0x10
+
+        .globl  bar
+        .data
+        .type   bar, %object
+bar:
+        .dc.a   __start_scnfoo
diff --git a/ld/testsuite/ld-elf/pr21562a.t b/ld/testsuite/ld-elf/pr21562a.t
new file mode 100644
index 00000000000..5e05ab3302d
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr21562a.t
@@ -0,0 +1,3 @@
+SECTIONS {
+	scnfoo : { *(scnfoo) }
+}
diff --git a/ld/testsuite/ld-elf/pr21562b.d b/ld/testsuite/ld-elf/pr21562b.d
new file mode 100644
index 00000000000..a03dbad6a05
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr21562b.d
@@ -0,0 +1,9 @@
+#ld: -shared -z defs --gc-sections
+#readelf: -s -S --wide
+#target: *-*-linux* *-*-gnu*
+
+#...
+  \[[ 0-9]+\] scnfoo[ \t]+PROGBITS[ \t]+[0-9a-f]+ +[0-9a-f]+ +0*10[ \t]+.*
+#...
+ +[0-9]+: +[0-9a-f]+ +[0-9a-f]+ +NOTYPE +LOCAL +DEFAULT +[0-9]+ +__stop_scnfoo
+#pass
diff --git a/ld/testsuite/ld-elf/pr21562b.s b/ld/testsuite/ld-elf/pr21562b.s
new file mode 100644
index 00000000000..1732ee24b20
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr21562b.s
@@ -0,0 +1,8 @@
+        .section        scnfoo,"aw",%progbits
+        .zero 0x10
+
+        .globl  bar
+        .data
+        .type   bar, %object
+bar:
+        .dc.a   __stop_scnfoo
diff --git a/ld/testsuite/ld-elf/pr21562b.t b/ld/testsuite/ld-elf/pr21562b.t
new file mode 100644
index 00000000000..b30b521d40b
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr21562b.t
@@ -0,0 +1,5 @@
+SECTIONS {
+	PROVIDE (__start_scnfoo = .);
+	scnfoo : { *(scnfoo) }
+	PROVIDE (__stop_scnfoo = .);
+}
diff --git a/ld/testsuite/ld-elf/pr21562c.d b/ld/testsuite/ld-elf/pr21562c.d
new file mode 100644
index 00000000000..9de035faac6
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr21562c.d
@@ -0,0 +1,10 @@
+#source: pr21562a.s
+#ld: -shared -z defs --gc-sections -T pr21562a.t
+#readelf: -s -S --wide
+#target: *-*-linux* *-*-gnu*
+
+#...
+  \[[ 0-9]+\] scnfoo[ \t]+PROGBITS[ \t]+[0-9a-f]+ +[0-9a-f]+ +0*10[ \t]+.*
+#...
+ +[0-9]+: +[0-9a-f]+ +[0-9a-f]+ +NOTYPE +LOCAL +DEFAULT +[0-9]+ +__start_scnfoo
+#pass
diff --git a/ld/testsuite/ld-elf/pr21562c.t b/ld/testsuite/ld-elf/pr21562c.t
new file mode 100644
index 00000000000..f9cb901afb6
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr21562c.t
@@ -0,0 +1,7 @@
+SECTIONS {
+    .foo : {
+	PROVIDE (__start_scnfoo = .);
+	*(scnfoo)
+	PROVIDE (__stop_scnfoo = .);
+    }
+}
diff --git a/ld/testsuite/ld-elf/pr21562d.d b/ld/testsuite/ld-elf/pr21562d.d
new file mode 100644
index 00000000000..e5344eff805
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr21562d.d
@@ -0,0 +1,10 @@
+#source: pr21562b.s
+#ld: -shared -z defs --gc-sections -T pr21562a.t
+#readelf: -s -S --wide
+#target: *-*-linux* *-*-gnu*
+
+#...
+  \[[ 0-9]+\] scnfoo[ \t]+PROGBITS[ \t]+[0-9a-f]+ +[0-9a-f]+ +0*10[ \t]+.*
+#...
+ +[0-9]+: +[0-9a-f]+ +[0-9a-f]+ +NOTYPE +LOCAL +DEFAULT +[0-9]+ +__stop_scnfoo
+#pass
diff --git a/ld/testsuite/ld-elf/pr21562d.t b/ld/testsuite/ld-elf/pr21562d.t
new file mode 100644
index 00000000000..c0cea61f069
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr21562d.t
@@ -0,0 +1,5 @@
+SECTIONS {
+	PROVIDE (__start_scnfoo = .);
+	.foo : { *(scnfoo) }
+	PROVIDE (__stop_scnfoo = .);
+}
diff --git a/ld/testsuite/ld-elf/pr21562e.d b/ld/testsuite/ld-elf/pr21562e.d
new file mode 100644
index 00000000000..afaf7e56a61
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr21562e.d
@@ -0,0 +1,10 @@
+#source: pr21562a.s
+#ld: -shared -z defs
+#readelf: -s -S --wide
+#target: *-*-linux* *-*-gnu*
+
+#...
+  \[[ 0-9]+\] scnfoo[ \t]+PROGBITS[ \t]+[0-9a-f]+ +[0-9a-f]+ +0*10[ \t]+.*
+#...
+ +[0-9]+: +[0-9a-f]+ +[0-9a-f]+ +NOTYPE +LOCAL +DEFAULT +[0-9]+ +__start_scnfoo
+#pass
diff --git a/ld/testsuite/ld-elf/pr21562f.d b/ld/testsuite/ld-elf/pr21562f.d
new file mode 100644
index 00000000000..b9c324a47d2
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr21562f.d
@@ -0,0 +1,10 @@
+#source: pr21562b.s
+#ld: -shared -z defs
+#readelf: -s -S --wide
+#target: *-*-linux* *-*-gnu*
+
+#...
+  \[[ 0-9]+\] scnfoo[ \t]+PROGBITS[ \t]+[0-9a-f]+ +[0-9a-f]+ +0*10[ \t]+.*
+#...
+ +[0-9]+: +[0-9a-f]+ +[0-9a-f]+ +NOTYPE +LOCAL +DEFAULT +[0-9]+ +__stop_scnfoo
+#pass
diff --git a/ld/testsuite/ld-elf/pr21562g.d b/ld/testsuite/ld-elf/pr21562g.d
new file mode 100644
index 00000000000..a813594d275
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr21562g.d
@@ -0,0 +1,10 @@
+#source: pr21562a.s
+#ld: -shared -z defs -T pr21562a.t
+#readelf: -s -S --wide
+#target: *-*-linux* *-*-gnu*
+
+#...
+  \[[ 0-9]+\] scnfoo[ \t]+PROGBITS[ \t]+[0-9a-f]+ +[0-9a-f]+ +0*10[ \t]+.*
+#...
+ +[0-9]+: +[0-9a-f]+ +[0-9a-f]+ +NOTYPE +LOCAL +DEFAULT +[0-9]+ +__start_scnfoo
+#pass
diff --git a/ld/testsuite/ld-elf/pr21562h.d b/ld/testsuite/ld-elf/pr21562h.d
new file mode 100644
index 00000000000..6adabd7ba4f
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr21562h.d
@@ -0,0 +1,10 @@
+#source: pr21562b.s
+#ld: -shared -z defs -T pr21562a.t
+#readelf: -s -S --wide
+#target: *-*-linux* *-*-gnu*
+
+#...
+  \[[ 0-9]+\] scnfoo[ \t]+PROGBITS[ \t]+[0-9a-f]+ +[0-9a-f]+ +0*10[ \t]+.*
+#...
+ +[0-9]+: +[0-9a-f]+ +[0-9a-f]+ +NOTYPE +LOCAL +DEFAULT +[0-9]+ +__stop_scnfoo
+#pass
diff --git a/ld/testsuite/ld-elf/pr21562i.d b/ld/testsuite/ld-elf/pr21562i.d
new file mode 100644
index 00000000000..49eb2ecb647
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr21562i.d
@@ -0,0 +1,10 @@
+#source: pr21562a.s
+#ld: -shared -z defs --gc-sections -T pr21562b.t
+#readelf: -s -S --wide
+#target: *-*-linux* *-*-gnu*
+
+#...
+  \[[ 0-9]+\] scnfoo[ \t]+PROGBITS[ \t]+[0-9a-f]+ +[0-9a-f]+ +0*10[ \t]+.*
+#...
+ +[0-9]+: +[0-9a-f]+ +[0-9a-f]+ +NOTYPE +LOCAL +DEFAULT +[0-9]+ +__start_scnfoo
+#pass
diff --git a/ld/testsuite/ld-elf/pr21562j.d b/ld/testsuite/ld-elf/pr21562j.d
new file mode 100644
index 00000000000..14bb03587d1
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr21562j.d
@@ -0,0 +1,10 @@
+#source: pr21562b.s
+#ld: -shared -z defs --gc-sections -T pr21562b.t
+#readelf: -s -S --wide
+#target: *-*-linux* *-*-gnu*
+
+#...
+  \[[ 0-9]+\] scnfoo[ \t]+PROGBITS[ \t]+[0-9a-f]+ +[0-9a-f]+ +0*10[ \t]+.*
+#...
+ +[0-9]+: +[0-9a-f]+ +[0-9a-f]+ +NOTYPE +LOCAL +DEFAULT +[0-9]+ +__stop_scnfoo
+#pass
diff --git a/ld/testsuite/ld-elf/pr21562k.d b/ld/testsuite/ld-elf/pr21562k.d
new file mode 100644
index 00000000000..1bf1e931775
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr21562k.d
@@ -0,0 +1,10 @@
+#source: pr21562a.s
+#ld: -shared -z defs --gc-sections -T pr21562c.t
+#readelf: -s -S --wide
+#target: *-*-linux* *-*-gnu*
+
+#...
+  \[[ 0-9]+\] \.foo[ \t]+PROGBITS[ \t]+[0-9a-f]+ +[0-9a-f]+ +0*10[ \t]+.*
+#...
+ +[0-9]+: +[0-9a-f]+ +[0-9a-f]+ +NOTYPE +LOCAL +DEFAULT +[0-9]+ +__start_scnfoo
+#pass
diff --git a/ld/testsuite/ld-elf/pr21562l.d b/ld/testsuite/ld-elf/pr21562l.d
new file mode 100644
index 00000000000..8297ec2b8ee
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr21562l.d
@@ -0,0 +1,10 @@
+#source: pr21562b.s
+#ld: -shared -z defs --gc-sections -T pr21562c.t
+#readelf: -s -S --wide
+#target: *-*-linux* *-*-gnu*
+
+#...
+  \[[ 0-9]+\] \.foo[ \t]+PROGBITS[ \t]+[0-9a-f]+ +[0-9a-f]+ +0*10[ \t]+.*
+#...
+ +[0-9]+: +[0-9a-f]+ +[0-9a-f]+ +NOTYPE +LOCAL +DEFAULT +[0-9]+ +__stop_scnfoo
+#pass
diff --git a/ld/testsuite/ld-elf/pr21562m.d b/ld/testsuite/ld-elf/pr21562m.d
new file mode 100644
index 00000000000..34f8df09aab
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr21562m.d
@@ -0,0 +1,10 @@
+#source: pr21562a.s
+#ld: -shared -z defs --gc-sections -T pr21562d.t
+#readelf: -s -S --wide
+#target: *-*-linux* *-*-gnu*
+
+#...
+  \[[ 0-9]+\] \.foo[ \t]+PROGBITS[ \t]+[0-9a-f]+ +[0-9a-f]+ +0*10[ \t]+.*
+#...
+ +[0-9]+: +[0-9a-f]+ +[0-9a-f]+ +NOTYPE +LOCAL +DEFAULT +[0-9]+ +__start_scnfoo
+#pass
diff --git a/ld/testsuite/ld-elf/pr21562n.d b/ld/testsuite/ld-elf/pr21562n.d
new file mode 100644
index 00000000000..e4b1919c670
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr21562n.d
@@ -0,0 +1,10 @@
+#source: pr21562b.s
+#ld: -shared -z defs --gc-sections -T pr21562d.t
+#readelf: -s -S --wide
+#target: *-*-linux* *-*-gnu*
+
+#...
+  \[[ 0-9]+\] \.foo[ \t]+PROGBITS[ \t]+[0-9a-f]+ +[0-9a-f]+ +0*10[ \t]+.*
+#...
+ +[0-9]+: +[0-9a-f]+ +[0-9a-f]+ +NOTYPE +LOCAL +DEFAULT +[0-9]+ +__stop_scnfoo
+#pass
diff --git a/ld/testsuite/ld-gc/gc.exp b/ld/testsuite/ld-gc/gc.exp
index ba5c46b64f8..364c73bf5d4 100644
--- a/ld/testsuite/ld-gc/gc.exp
+++ b/ld/testsuite/ld-gc/gc.exp
@@ -119,6 +119,12 @@ if { [is_elf_format] && [check_shared_lib_support] } then {
 	run_dump_test "personality"
     }
     run_dump_test "pr18223"
+    if {![ld_assemble_flags $as $gasopt $srcdir/$subdir/pr20022a.s tmpdir/pr20022a.o]
+	|| ![ld_link $ld tmpdir/pr20022.so "-shared --gc-sections tmpdir/pr20022a.o"] } then {
+	fail pr20022
+    } else {
+	run_dump_test "pr20022"
+    }
 }
 
 if { [is_remote host] || [which $CC] != 0 } {
diff --git a/ld/testsuite/ld-gc/pr19161.d b/ld/testsuite/ld-gc/pr19161.d
index c36e6638cd0..baee8da3af9 100644
--- a/ld/testsuite/ld-gc/pr19161.d
+++ b/ld/testsuite/ld-gc/pr19161.d
@@ -6,5 +6,5 @@
 #xfail: mips64vr-*-* msp430-*-* powerpc*-*-eabivle rl78-*-* rx-*-* sh*-*-*
 
 #...
-0*[1-9a-f]+[0-9a-f]*[ 	](D)[ 	]_*__start_my_section
+0*[1-9a-f]+[0-9a-f]*[ 	](d|D)[ 	]_*__start_my_section
 #...
diff --git a/ld/testsuite/ld-gc/pr20022.d b/ld/testsuite/ld-gc/pr20022.d
new file mode 100644
index 00000000000..b51ec1903fe
--- /dev/null
+++ b/ld/testsuite/ld-gc/pr20022.d
@@ -0,0 +1,11 @@
+#source: pr20022b.s
+#ld: --gc-sections -e _start tmpdir/pr20022.so
+#readelf: -SsW
+#target: *-*-linux* *-*-gnu*
+#notarget: *-*-*aout *-*-*oldld frv-*-linux* metag-*-linux*
+
+#...
+  \[[ 0-9]+\] _foo[ \t]+PROGBITS[ \t]+[0-9a-f]+ +[0-9a-f]+ +[0-9a-f]+[ \t]+.*
+#...
+ +[0-9]+: +[0-9a-f]+ +[0-9a-f]+ +NOTYPE +LOCAL +DEFAULT +[0-9]+ +__start__foo
+#pass
diff --git a/ld/testsuite/ld-gc/pr20022a.s b/ld/testsuite/ld-gc/pr20022a.s
new file mode 100644
index 00000000000..6bd346fe219
--- /dev/null
+++ b/ld/testsuite/ld-gc/pr20022a.s
@@ -0,0 +1,8 @@
+	.data
+	.globl bar
+	.type bar,%object
+bar:
+	.dc.a	__start__foo
+	.section _foo,"aw",%progbits
+foo:
+	.ascii "This is bar"
diff --git a/ld/testsuite/ld-gc/pr20022b.s b/ld/testsuite/ld-gc/pr20022b.s
new file mode 100644
index 00000000000..2306c59d765
--- /dev/null
+++ b/ld/testsuite/ld-gc/pr20022b.s
@@ -0,0 +1,8 @@
+	.text
+	.globl _start
+_start:
+	.dc.a	__start__foo
+	.dc.a	bar
+	.section _foo,"aw",%progbits
+foo:
+	.ascii "This is foo"
diff --git a/ld/testsuite/ld-gc/start.d b/ld/testsuite/ld-gc/start.d
index 18e74c109c0..9113b482043 100644
--- a/ld/testsuite/ld-gc/start.d
+++ b/ld/testsuite/ld-gc/start.d
@@ -5,5 +5,5 @@
 #notarget: *-*-*aout *-*-*oldld frv-*-linux* metag-*-linux*
 
 #...
-[0-9a-f]+ D +__start__foo
+[0-9a-f]+ d +__start__foo
 #...
diff --git a/ld/testsuite/ld-x86-64/lea1a.d b/ld/testsuite/ld-x86-64/lea1a.d
index 9b662cb839f..28ea4b93fcc 100644
--- a/ld/testsuite/ld-x86-64/lea1a.d
+++ b/ld/testsuite/ld-x86-64/lea1a.d
@@ -15,5 +15,5 @@ Disassembly of section .text:
 [ 	]*[a-f0-9]+:	48 8d 05 ([0-9a-f]{2} ){4} *	lea    -0x[a-f0-9]+\(%rip\),%rax        # [a-f0-9]+ <foo>
 [ 	]*[a-f0-9]+:	4c 8d 1d ([0-9a-f]{2} ){4} *	lea    0x[a-f0-9]+\(%rip\),%r11        # [a-f0-9]+ <bar>
 [ 	]*[a-f0-9]+:	48 8d 05 ([0-9a-f]{2} ){4} *	lea    0x[a-f0-9]+\(%rip\),%rax        # [a-f0-9]+ <__start_my_section>
-[ 	]*[a-f0-9]+:	4c 8d 1d ([0-9a-f]{2} ){4} *	lea    0x[a-f0-9]+\(%rip\),%r11        # [a-f0-9]+ <__stop_my_section>
+[ 	]*[a-f0-9]+:	4c 8d 1d ([0-9a-f]{2} ){4} *	lea    0x[a-f0-9]+\(%rip\),%r11        # [a-f0-9]+ <.*>
 #pass
diff --git a/ld/testsuite/ld-x86-64/lea1b.d b/ld/testsuite/ld-x86-64/lea1b.d
index 9108149b3a3..c7873cd97bd 100644
--- a/ld/testsuite/ld-x86-64/lea1b.d
+++ b/ld/testsuite/ld-x86-64/lea1b.d
@@ -15,5 +15,5 @@ Disassembly of section .text:
 [ 	]*[a-f0-9]+:	48 8d 05 ([0-9a-f]{2} ){4} *	lea    -0x[a-f0-9]+\(%rip\),%rax        # [a-f0-9]+ <foo>
 [ 	]*[a-f0-9]+:	4c 8d 1d ([0-9a-f]{2} ){4} *	lea    0x[a-f0-9]+\(%rip\),%r11        # [a-f0-9]+ <bar>
 [ 	]*[a-f0-9]+:	48 8d 05 ([0-9a-f]{2} ){4} *	lea    0x[a-f0-9]+\(%rip\),%rax        # [a-f0-9]+ <__start_my_section>
-[ 	]*[a-f0-9]+:	4c 8d 1d ([0-9a-f]{2} ){4} *	lea    0x[a-f0-9]+\(%rip\),%r11        # [a-f0-9]+ <__stop_my_section>
+[ 	]*[a-f0-9]+:	4c 8d 1d ([0-9a-f]{2} ){4} *	lea    0x[a-f0-9]+\(%rip\),%r11        # [a-f0-9]+ <.*>
 #pass
diff --git a/ld/testsuite/ld-x86-64/lea1d.d b/ld/testsuite/ld-x86-64/lea1d.d
index 4d708d22c3a..70fc603894d 100644
--- a/ld/testsuite/ld-x86-64/lea1d.d
+++ b/ld/testsuite/ld-x86-64/lea1d.d
@@ -15,5 +15,5 @@ Disassembly of section .text:
 [ 	]*[a-f0-9]+:	48 8d 05 ([0-9a-f]{2} ){4} *	lea    -0x[a-f0-9]+\(%rip\),%rax        # [a-f0-9]+ <foo>
 [ 	]*[a-f0-9]+:	4c 8d 1d ([0-9a-f]{2} ){4} *	lea    0x[a-f0-9]+\(%rip\),%r11        # [a-f0-9]+ <bar>
 [ 	]*[a-f0-9]+:	48 8d 05 ([0-9a-f]{2} ){4} *	lea    0x[a-f0-9]+\(%rip\),%rax        # [a-f0-9]+ <__start_my_section>
-[ 	]*[a-f0-9]+:	4c 8d 1d ([0-9a-f]{2} ){4} *	lea    0x[a-f0-9]+\(%rip\),%r11        # [a-f0-9]+ <__stop_my_section>
+[ 	]*[a-f0-9]+:	4c 8d 1d ([0-9a-f]{2} ){4} *	lea    0x[a-f0-9]+\(%rip\),%r11        # [a-f0-9]+ <.*>
 #pass
diff --git a/ld/testsuite/ld-x86-64/lea1e.d b/ld/testsuite/ld-x86-64/lea1e.d
index da601379181..123fcd243c9 100644
--- a/ld/testsuite/ld-x86-64/lea1e.d
+++ b/ld/testsuite/ld-x86-64/lea1e.d
@@ -15,5 +15,5 @@ Disassembly of section .text:
 [ 	]*[a-f0-9]+:	48 8d 05 ([0-9a-f]{2} ){4} *	lea    -0x[a-f0-9]+\(%rip\),%rax        # [a-f0-9]+ <foo>
 [ 	]*[a-f0-9]+:	4c 8d 1d ([0-9a-f]{2} ){4} *	lea    0x[a-f0-9]+\(%rip\),%r11        # [a-f0-9]+ <bar>
 [ 	]*[a-f0-9]+:	48 8d 05 ([0-9a-f]{2} ){4} *	lea    0x[a-f0-9]+\(%rip\),%rax        # [a-f0-9]+ <__start_my_section>
-[ 	]*[a-f0-9]+:	4c 8d 1d ([0-9a-f]{2} ){4} *	lea    0x[a-f0-9]+\(%rip\),%r11        # [a-f0-9]+ <__stop_my_section>
+[ 	]*[a-f0-9]+:	4c 8d 1d ([0-9a-f]{2} ){4} *	lea    0x[a-f0-9]+\(%rip\),%r11        # [a-f0-9]+ <.*>
 #pass
-- 
2.30.2