[binutils-gdb] PR25236, common sym versioning

[Alan Modra]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=5fa370e437f39bf73a133cc84c4e6329943522bf

commit 5fa370e437f39bf73a133cc84c4e6329943522bf
Author: Alan Modra <amodra@gmail.com>
Date:   Fri Dec 6 11:21:45 2019 +1030

    PR25236, common sym versioning
    
    In cases where a relocatable object file has a common symbol, no other
    file has a definition, and there is a matching common symbol found in
    a shared library then ld will output a definition using the largest of
    size and alignment for the commons.  This patch fixes a bug in ld that
    ignored common symbols when assigning versions, resulting in such
    symbols being given VER_NDX_LOCAL versions.
    
    	PR 25236
    	* elflink.c (_bfd_elf_link_assign_sym_version): Assign versions
    	for ELF_COMMON_DEF_P symbols.
    	(elf_link_output_extsym, _bfd_elf_add_default_symbol): Adjust to
    	suit.

Diff:
---
 bfd/ChangeLog | 8 ++++++++
 bfd/elflink.c | 6 +++---
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index c1bba0c..50c878b 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,11 @@
+2019-12-07  Alan Modra  <amodra@gmail.com>
+
+	PR 25236
+	* elflink.c (_bfd_elf_link_assign_sym_version): Assign versions
+	for ELF_COMMON_DEF_P symbols.
+	(elf_link_output_extsym, _bfd_elf_add_default_symbol): Adjust to
+	suit.
+
 2019-12-05  Sandra Loosemore  <sandra@codesourcery.com>
 
 	Only give FDE encoding warnings if --eh-frame-hdr was specified.
diff --git a/bfd/elflink.c b/bfd/elflink.c
index 5549361..7078a2f 100644
--- a/bfd/elflink.c
+++ b/bfd/elflink.c
@@ -1904,7 +1904,7 @@ _bfd_elf_add_default_symbol (bfd *abfd,
   if (skip)
     goto nondefault;
 
-  if (hi->def_regular)
+  if (hi->def_regular || ELF_COMMON_DEF_P (hi))
     {
       /* If the undecorated symbol will have a version added by a
 	 script different to H, then don't indirect to/from the
@@ -2367,7 +2367,7 @@ _bfd_elf_link_assign_sym_version (struct elf_link_hash_entry *h, void *data)
 
   /* We only need version numbers for symbols defined in regular
      objects.  */
-  if (!h->def_regular)
+  if (!h->def_regular && !ELF_COMMON_DEF_P (h))
     {
       /* Hide symbols defined in discarded input sections.  */
       if ((h->root.type == bfd_link_hash_defined
@@ -10246,7 +10246,7 @@ elf_link_output_extsym (struct bfd_hash_entry *bh, void *data)
 	  Elf_Internal_Versym iversym;
 	  Elf_External_Versym *eversym;
 
-	  if (!h->def_regular)
+	  if (!h->def_regular && !ELF_COMMON_DEF_P (h))
 	    {
 	      if (h->verinfo.verdef == NULL
 		  || (elf_dyn_lib_class (h->verinfo.verdef->vd_bfd)