Add dynamic_undefined_weak.shusers/hjl/pr19704

19 files changed, 45 insertions, 3 deletions

diff --git a/bfd/elf-bfd.h b/bfd/elf-bfd.h
index e8a4dd51f7a..54d2fbdf5b1 100644
--- a/bfd/elf-bfd.h
+++ b/bfd/elf-bfd.h
@@ -1434,6 +1434,10 @@ struct elf_backend_data
   /* Address of protected data defined in the shared library may be
      external, i.e., due to copy relocation.   */
   unsigned extern_protected_data : 1;
+
+  /* Undefined weak symbol in the executable is dynamic, i.e, requires
+     dynamic relocation.  */
+  unsigned dynamic_undefined_weak : 1;
 };
 
 /* Information about reloc sections associated with a bfd_elf_section_data
diff --git a/bfd/elf32-i386.c b/bfd/elf32-i386.c
index a8951d8d586..59ddfe2b675 100644
--- a/bfd/elf32-i386.c
+++ b/bfd/elf32-i386.c
@@ -5768,6 +5768,7 @@ elf_i386_add_symbol_hook (bfd * abfd,
 #define elf_backend_got_header_size	12
 #define elf_backend_plt_alignment	4
 #define elf_backend_extern_protected_data 1
+#define elf_backend_dynamic_undefined_weak 0
 
 /* Support RELA for objdump of prelink objects.  */
 #define elf_info_to_howto		      elf_i386_info_to_howto_rel
diff --git a/bfd/elf64-x86-64.c b/bfd/elf64-x86-64.c
index 8fb2232f90a..274cf489a40 100644
--- a/bfd/elf64-x86-64.c
+++ b/bfd/elf64-x86-64.c
@@ -6360,6 +6360,7 @@ static const struct bfd_elf_special_section
 #define elf_backend_rela_normal		    1
 #define elf_backend_plt_alignment           4
 #define elf_backend_extern_protected_data   1
+#define elf_backend_dynamic_undefined_weak  0
 
 #define elf_info_to_howto		    elf_x86_64_info_to_howto
 
diff --git a/bfd/elfxx-target.h b/bfd/elfxx-target.h
index b3227ed3c52..f35d5d07b4a 100644
--- a/bfd/elfxx-target.h
+++ b/bfd/elfxx-target.h
@@ -120,6 +120,9 @@
 #ifndef elf_backend_extern_protected_data
 #define elf_backend_extern_protected_data 0
 #endif
+#ifndef elf_backend_dynamic_undefined_weak
+#define elf_backend_dynamic_undefined_weak 1
+#endif
 #ifndef elf_backend_stack_align
 #define elf_backend_stack_align 16
 #endif
@@ -824,7 +827,8 @@ static struct elf_backend_data elfNN_bed =
   elf_backend_want_p_paddr_set_to_zero,
   elf_backend_default_execstack,
   elf_backend_caches_rawsize,
-  elf_backend_extern_protected_data
+  elf_backend_extern_protected_data,
+  elf_backend_dynamic_undefined_weak
 };
 
 /* Forward declaration for use when initialising alternative_target field.  */
diff --git a/include/bfdlink.h b/include/bfdlink.h
index 9b849aa761e..860811c2a78 100644
--- a/include/bfdlink.h
+++ b/include/bfdlink.h
@@ -542,6 +542,10 @@ struct bfd_link_info
      backend to decide.  */
   int extern_protected_data;
 
+  /* > 0 to treat undefined weak symbol in the executable as dynamic,
+     requiring dynamic relocation.  */
+  int dynamic_undefined_weak;
+
   /* Non-zero if auto-import thunks for DATA items in pei386 DLLs
      should be generated/linked against.  Set to 1 if this feature
      is explicitly requested by the user, -1 if enabled by default.  */
diff --git a/ld/Makefile.am b/ld/Makefile.am
index 7339298fa99..4a8c0b6e875 100644
--- a/ld/Makefile.am
+++ b/ld/Makefile.am
@@ -671,6 +671,7 @@ ELF_DEPS = $(srcdir)/emultempl/elf32.em $(srcdir)/emultempl/elf-generic.em $(src
 ELF_GEN_DEPS = $(srcdir)/emultempl/generic.em $(srcdir)/emultempl/elf-generic.em $(srcdir)/emultempl/genelf.em $(srcdir)/scripttempl/DWARF.sc
 ELF_X86_DEPS = $(ELF_DEPS) $(srcdir)/emulparams/plt_unwind.sh \
 	       $(srcdir)/emulparams/extern_protected_data.sh \
+	       $(srcdir)/emulparams/dynamic_undefined_weak.sh \
 	       $(srcdir)/emulparams/call_nop.sh
 
 @TDIRS@
diff --git a/ld/Makefile.in b/ld/Makefile.in
index 8803e22c7fa..45388d7bacf 100644
--- a/ld/Makefile.in
+++ b/ld/Makefile.in
@@ -887,6 +887,7 @@ ELF_DEPS = $(srcdir)/emultempl/elf32.em $(srcdir)/emultempl/elf-generic.em $(src
 ELF_GEN_DEPS = $(srcdir)/emultempl/generic.em $(srcdir)/emultempl/elf-generic.em $(srcdir)/emultempl/genelf.em $(srcdir)/scripttempl/DWARF.sc
 ELF_X86_DEPS = $(ELF_DEPS) $(srcdir)/emulparams/plt_unwind.sh \
 	       $(srcdir)/emulparams/extern_protected_data.sh \
+	       $(srcdir)/emulparams/dynamic_undefined_weak.sh \
 	       $(srcdir)/emulparams/call_nop.sh
 
 
diff --git a/ld/emulparams/dynamic_undefined_weak.sh b/ld/emulparams/dynamic_undefined_weak.sh
new file mode 100644
index 00000000000..c6d99052a04
--- /dev/null
+++ b/ld/emulparams/dynamic_undefined_weak.sh
@@ -0,0 +1,12 @@
+PARSE_AND_LIST_OPTIONS_DYNAMIC_UNDEFINED_WEAK='
+  fprintf (file, _("\
+  -z dynamic-undefined-weak   Treat undefined weak symbol as dynamic\n"));
+'
+
+PARSE_AND_LIST_ARGS_CASE_Z_DYNAMIC_UNDEFINED_WEAK='
+      else if (strcmp (optarg, "dynamic-undefined-weak") == 0)
+	link_info.dynamic_undefined_weak = TRUE;
+'
+
+PARSE_AND_LIST_OPTIONS="$PARSE_AND_LIST_OPTIONS $PARSE_AND_LIST_OPTIONS_DYNAMIC_UNDEFINED_WEAK"
+PARSE_AND_LIST_ARGS_CASE_Z="$PARSE_AND_LIST_ARGS_CASE_Z $PARSE_AND_LIST_ARGS_CASE_Z_DYNAMIC_UNDEFINED_WEAK"
diff --git a/ld/emulparams/elf32_x86_64.sh b/ld/emulparams/elf32_x86_64.sh
index 0a035483923..1b285c559a1 100644
--- a/ld/emulparams/elf32_x86_64.sh
+++ b/ld/emulparams/elf32_x86_64.sh
@@ -1,5 +1,6 @@
 . ${srcdir}/emulparams/plt_unwind.sh
 . ${srcdir}/emulparams/extern_protected_data.sh
+. ${srcdir}/emulparams/dynamic_undefined_weak.sh
 . ${srcdir}/emulparams/call_nop.sh
 SCRIPT_NAME=elf
 ELFSIZE=32
diff --git a/ld/emulparams/elf_i386.sh b/ld/emulparams/elf_i386.sh
index 7dceea9a2dd..3451bb2b1ea 100644
--- a/ld/emulparams/elf_i386.sh
+++ b/ld/emulparams/elf_i386.sh
@@ -1,5 +1,6 @@
 . ${srcdir}/emulparams/plt_unwind.sh
 . ${srcdir}/emulparams/extern_protected_data.sh
+. ${srcdir}/emulparams/dynamic_undefined_weak.sh
 . ${srcdir}/emulparams/call_nop.sh
 SCRIPT_NAME=elf
 OUTPUT_FORMAT="elf32-i386"
diff --git a/ld/emulparams/elf_i386_be.sh b/ld/emulparams/elf_i386_be.sh
index 40ed8c6608b..70db4432395 100644
--- a/ld/emulparams/elf_i386_be.sh
+++ b/ld/emulparams/elf_i386_be.sh
@@ -1,4 +1,5 @@
 . ${srcdir}/emulparams/extern_protected_data.sh
+. ${srcdir}/emulparams/dynamic_undefined_weak.sh
 . ${srcdir}/emulparams/call_nop.sh
 SCRIPT_NAME=elf
 OUTPUT_FORMAT="elf32-i386"
diff --git a/ld/emulparams/elf_i386_chaos.sh b/ld/emulparams/elf_i386_chaos.sh
index 33757bfd9e1..aa36cb51c2d 100644
--- a/ld/emulparams/elf_i386_chaos.sh
+++ b/ld/emulparams/elf_i386_chaos.sh
@@ -1,5 +1,6 @@
 . ${srcdir}/emulparams/plt_unwind.sh
 . ${srcdir}/emulparams/extern_protected_data.sh
+. ${srcdir}/emulparams/dynamic_undefined_weak.sh
 . ${srcdir}/emulparams/call_nop.sh
 SCRIPT_NAME=elf_chaos
 OUTPUT_FORMAT="elf32-i386"
diff --git a/ld/emulparams/elf_i386_ldso.sh b/ld/emulparams/elf_i386_ldso.sh
index f7805819b9b..1328520c57c 100644
--- a/ld/emulparams/elf_i386_ldso.sh
+++ b/ld/emulparams/elf_i386_ldso.sh
@@ -1,5 +1,6 @@
 . ${srcdir}/emulparams/plt_unwind.sh
 . ${srcdir}/emulparams/extern_protected_data.sh
+. ${srcdir}/emulparams/dynamic_undefined_weak.sh
 . ${srcdir}/emulparams/call_nop.sh
 SCRIPT_NAME=elf
 OUTPUT_FORMAT="elf32-i386"
diff --git a/ld/emulparams/elf_i386_vxworks.sh b/ld/emulparams/elf_i386_vxworks.sh
index cb289e6307d..aaea8c48743 100644
--- a/ld/emulparams/elf_i386_vxworks.sh
+++ b/ld/emulparams/elf_i386_vxworks.sh
@@ -12,4 +12,5 @@ GENERATE_PIE_SCRIPT=yes
 NO_SMALL_DATA=yes
 . ${srcdir}/emulparams/vxworks.sh
 . ${srcdir}/emulparams/extern_protected_data.sh
+. ${srcdir}/emulparams/dynamic_undefined_weak.sh
 . ${srcdir}/emulparams/call_nop.sh
diff --git a/ld/emulparams/elf_iamcu.sh b/ld/emulparams/elf_iamcu.sh
index 5fae6515ea3..863027b57b4 100644
--- a/ld/emulparams/elf_iamcu.sh
+++ b/ld/emulparams/elf_iamcu.sh
@@ -1,5 +1,6 @@
 . ${srcdir}/emulparams/plt_unwind.sh
 . ${srcdir}/emulparams/extern_protected_data.sh
+. ${srcdir}/emulparams/dynamic_undefined_weak.sh
 . ${srcdir}/emulparams/call_nop.sh
 SCRIPT_NAME=elf
 OUTPUT_FORMAT="elf32-iamcu"
diff --git a/ld/emulparams/elf_k1om.sh b/ld/emulparams/elf_k1om.sh
index 289274daca6..494efcc6c90 100644
--- a/ld/emulparams/elf_k1om.sh
+++ b/ld/emulparams/elf_k1om.sh
@@ -1,5 +1,6 @@
 . ${srcdir}/emulparams/plt_unwind.sh
 . ${srcdir}/emulparams/extern_protected_data.sh
+. ${srcdir}/emulparams/dynamic_undefined_weak.sh
 . ${srcdir}/emulparams/call_nop.sh
 SCRIPT_NAME=elf
 ELFSIZE=64
diff --git a/ld/emulparams/elf_l1om.sh b/ld/emulparams/elf_l1om.sh
index 17fa8e2579c..b1158791f46 100644
--- a/ld/emulparams/elf_l1om.sh
+++ b/ld/emulparams/elf_l1om.sh
@@ -1,5 +1,6 @@
 . ${srcdir}/emulparams/plt_unwind.sh
 . ${srcdir}/emulparams/extern_protected_data.sh
+. ${srcdir}/emulparams/dynamic_undefined_weak.sh
 . ${srcdir}/emulparams/call_nop.sh
 SCRIPT_NAME=elf
 ELFSIZE=64
diff --git a/ld/emulparams/elf_x86_64.sh b/ld/emulparams/elf_x86_64.sh
index 5d31da1ba1b..0159a6ca44c 100644
--- a/ld/emulparams/elf_x86_64.sh
+++ b/ld/emulparams/elf_x86_64.sh
@@ -1,5 +1,6 @@
 . ${srcdir}/emulparams/plt_unwind.sh
 . ${srcdir}/emulparams/extern_protected_data.sh
+. ${srcdir}/emulparams/dynamic_undefined_weak.sh
 . ${srcdir}/emulparams/call_nop.sh
 SCRIPT_NAME=elf
 ELFSIZE=64
diff --git a/ld/emulparams/extern_protected_data.sh b/ld/emulparams/extern_protected_data.sh
index fd4bd3b3c82..65c68adb0b2 100644
--- a/ld/emulparams/extern_protected_data.sh
+++ b/ld/emulparams/extern_protected_data.sh
@@ -1,9 +1,13 @@
-PARSE_AND_LIST_OPTIONS='
+PARSE_AND_LIST_OPTIONS_NOEXTEN_PROTECTED_DATA='
   fprintf (file, _("\
   -z noextern-protected-data  Do not treat protected data symbol as external\n"));
 '
 
-PARSE_AND_LIST_ARGS_CASE_Z='
+PARSE_AND_LIST_ARGS_CASE_Z_NOEXTEN_PROTECTED_DATA='
       else if (strcmp (optarg, "noextern-protected-data") == 0)
 	link_info.extern_protected_data = FALSE;
 '
+
+
+PARSE_AND_LIST_OPTIONS="$PARSE_AND_LIST_OPTIONS $PARSE_AND_LIST_OPTIONS_NOEXTEN_PROTECTED_DATA"
+PARSE_AND_LIST_ARGS_CASE_Z="$PARSE_AND_LIST_ARGS_CASE_Z $PARSE_AND_LIST_ARGS_CASE_Z_NOEXTEN_PROTECTED_DATA"