x86: Properly handle __ehdr_start

After _bfd_i386_elf_convert_load and _bfd_x86_64_elf_convert_load are
removed, elf_i386_convert_load_reloc and elf_x86_64_convert_load_reloc
see __ehdr_start as an undefined symbol when they are called from
check_relocs to convert GOT relocations against local symbols.  But
__ehdr_start will be defined as a hidden symbol by linker at the later
stage if it is referenced.  This patch marks __ehdr_start as a defined
local symbol at the start of check_relocs if it is referenced and not
defined.

bfd/

	PR ld/22115
	* elf32-i386.c (elf_i386_convert_load_reloc): Check linker_def.
	Don't use UNDEFINED_WEAK_RESOLVED_TO_ZERO.
	* elf64-x86-64.c (elf_x86_64_convert_load_reloc): Check
	linker_def.  Don't use UNDEFINED_WEAK_RESOLVED_TO_ZERO.
	* elfxx-x86.c (_bfd_x86_elf_link_check_relocs): Set local_ref
	and linker_def on __ehdr_start if it is referenced and not
	defined.
	(_bfd_x86_elf_link_symbol_references_local): Also set local_ref
	and return TRUE when building executable, if a symbol has
	non-GOT/non-PLT relocations in text section or there is no
	dynamic linker.
	* elfxx-x86.h (elf_x86_link_hash_entry): Add linker_def.

ld/

	PR ld/22115
	* ld-i386/i386.exp: Run PR ld/22115 tests,
	* ld/testsuite/ld-x86-64/x86-64.exp: Likewise.
	* testsuite/ld-i386/pr22115-1.s: New file.
	* testsuite/ld-i386/pr22115-1a.d: Likewise.
	* testsuite/ld-i386/pr22115-1b.d: Likewise.
	* testsuite/ld-i386/pr22115-1c.d: Likewise.
	* testsuite/ld-i386/pr22115-1d.d: Likewise.
	* testsuite/ld-x86-64/pr22115-1.s: Likewise.
	* testsuite/ld-x86-64/pr22115-1a-x32.d: Likewise.
	* testsuite/ld-x86-64/pr22115-1a.d: Likewise.
	* testsuite/ld-x86-64/pr22115-1b-x32.d: Likewise.
	* testsuite/ld-x86-64/pr22115-1b.d: Likewise.
	* testsuite/ld-x86-64/pr22115-1c-x32.d: Likewise.
	* testsuite/ld-x86-64/pr22115-1c.d: Likewise.
	* testsuite/ld-x86-64/pr22115-1d-x32.d: Likewise.
	* testsuite/ld-x86-64/pr22115-1d.d: Likewise.

1 files changed, 34 insertions, 11 deletions

diff --git a/bfd/elfxx-x86.c b/bfd/elfxx-x86.c
index 86e26f9..e056c3c 100644
--- a/bfd/elfxx-x86.c
+++ b/bfd/elfxx-x86.c
@@ -845,12 +845,28 @@ _bfd_x86_elf_link_check_relocs (bfd *abfd, struct bfd_link_info *info)
       htab = elf_x86_hash_table (info, bed->target_id);
       if (htab)
 	{
-	  struct elf_link_hash_entry *h
-	    = elf_link_hash_lookup (elf_hash_table (info),
+	  struct elf_link_hash_entry *h;
+
+	  h = elf_link_hash_lookup (elf_hash_table (info),
 				    htab->tls_get_addr,
 				    FALSE, FALSE, FALSE);
 	  if (h != NULL)
-	    ((struct elf_x86_link_hash_entry *) h)->tls_get_addr = 1;
+	    elf_x86_hash_entry (h)->tls_get_addr = 1;
+
+	  /* "__ehdr_start" will be defined by linker as a hidden symbol
+	     later if it is referenced and not defined.  */
+	  h = elf_link_hash_lookup (elf_hash_table (info),
+				    "__ehdr_start",
+				    FALSE, FALSE, FALSE);
+	  if (h != NULL
+	      && (h->root.type == bfd_link_hash_new
+		  || h->root.type == bfd_link_hash_undefined
+		  || h->root.type == bfd_link_hash_undefweak
+		  || h->root.type == bfd_link_hash_common))
+	    {
+	      elf_x86_hash_entry (h)->local_ref = 2;
+	      elf_x86_hash_entry (h)->linker_def = 1;
+	    }
 	}
     }
 
@@ -1671,8 +1687,9 @@ bfd_boolean
 _bfd_x86_elf_link_symbol_references_local (struct bfd_link_info *info,
 					   struct elf_link_hash_entry *h)
 {
-  struct elf_x86_link_hash_entry *eh
-    = (struct elf_x86_link_hash_entry *) h;
+  struct elf_x86_link_hash_entry *eh = elf_x86_hash_entry (h);
+  struct elf_x86_link_hash_table *htab
+    = (struct elf_x86_link_hash_table *) info->hash;
 
   if (eh->local_ref > 1)
     return TRUE;
@@ -1681,13 +1698,19 @@ _bfd_x86_elf_link_symbol_references_local (struct bfd_link_info *info,
     return FALSE;
 
   /* Unversioned symbols defined in regular objects can be forced local
-     by linker version script.  A weak undefined symbol can fored local
-     if it has non-default visibility or "-z nodynamic-undefined-weak"
-     is used.  */
+     by linker version script.  A weak undefined symbol is forced local
+     if
+     1. It has non-default visibility.  Or
+     2. When building executable, it has non-GOT/non-PLT relocations
+	in text section or there is no dynamic linker.  Or
+     3. or "-z nodynamic-undefined-weak" is used.
+   */
   if (SYMBOL_REFERENCES_LOCAL (info, h)
-      || ((ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
-	   || info->dynamic_undefined_weak == 0)
-	  && h->root.type == bfd_link_hash_undefweak)
+      || (h->root.type == bfd_link_hash_undefweak
+	  && (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
+	      || (bfd_link_executable (info)
+		  && (htab->interp == NULL || eh->has_non_got_reloc))
+	      || info->dynamic_undefined_weak == 0))
       || ((h->def_regular || ELF_COMMON_DEF_P (h))
 	  && h->versioned == unversioned
 	  && info->version_info != NULL