Fix internal error caused by conflicting default version definitions.

gold/
	PR gold/16504
	* dynobj.cc (Versions::symbol_section_contents): Don't set
	VERSYM_HIDDEN flag for undefined symbols.
	* symtab.cc (Symbol_table::add_from_object): Don't override default
	version definition with a different default version.
	* symtab.h (Symbol::from_dyn): New method.
	* testsuite/plugin_test.c (struct sym_info): Add ver field.
	(claim_file_hook): Pass symbol version to plugin API.
	(parse_readelf_line): Parse symbol version.
	* testsuite/Makefile.am (ver_test_pr16504): New test case.
	* testsuite/Makefile.in: Regenerate.
	* testsuite/ver_test_pr16504.sh: New test script.
	* testsuite/ver_test_pr16504_a.c: New source file.
	* testsuite/ver_test_pr16504_a.script: New version script.
	* testsuite/ver_test_pr16504_b.c: New source file.
	* testsuite/ver_test_pr16504_b.script: New version script.

1 files changed, 36 insertions, 11 deletions

diff --git a/gold/symtab.cc b/gold/symtab.cc
index 34551ac..238834d 100644
--- a/gold/symtab.cc
+++ b/gold/symtab.cc
@@ -989,7 +989,7 @@ Symbol_table::add_from_object(Object* object,
   // ins.first->second: the value (Symbol*).
   // ins.second: true if new entry was inserted, false if not.
 
-  Sized_symbol<size>* ret;
+  Sized_symbol<size>* ret = NULL;
   bool was_undefined_in_reg;
   bool was_common;
   if (!ins.second)
@@ -1049,17 +1049,42 @@ Symbol_table::add_from_object(Object* object,
 	  // it, then change it to NAME/VERSION.
 	  ret = this->get_sized_symbol<size>(insdefault.first->second);
 
-	  was_undefined_in_reg = ret->is_undefined() && ret->in_reg();
-	  // Commons from plugins are just placeholders.
-	  was_common = ret->is_common() && ret->object()->pluginobj() == NULL;
-
-	  this->resolve(ret, sym, st_shndx, is_ordinary, orig_st_shndx, object,
-			version, is_default_version);
-          if (parameters->options().gc_sections())
-            this->gc_mark_dyn_syms(ret);
-	  ins.first->second = ret;
+	  // If the existing symbol already has a version,
+	  // don't override it with the new symbol.
+	  // This should only happen when the new symbol
+	  // is from a shared library.
+	  if (ret->version() != NULL)
+	    {
+	      if (!object->is_dynamic())
+	        {
+		  gold_warning(_("%s: conflicting default version definition"
+				 " for %s@@%s"),
+			       object->name().c_str(), name, version);
+		  if (ret->source() == Symbol::FROM_OBJECT)
+		    gold_info(_("%s: %s: previous definition of %s@@%s here"),
+			      program_name,
+			      ret->object()->name().c_str(),
+			      name, ret->version());
+	        }
+	      ret = NULL;
+	      is_default_version = false;
+	    }
+	  else
+	    {
+	      was_undefined_in_reg = ret->is_undefined() && ret->in_reg();
+	      // Commons from plugins are just placeholders.
+	      was_common = (ret->is_common()
+			    && ret->object()->pluginobj() == NULL);
+
+	      this->resolve(ret, sym, st_shndx, is_ordinary, orig_st_shndx,
+			    object, version, is_default_version);
+	      if (parameters->options().gc_sections())
+		this->gc_mark_dyn_syms(ret);
+	      ins.first->second = ret;
+	    }
 	}
-      else
+
+      if (ret == NULL)
 	{
 	  was_undefined_in_reg = false;
 	  was_common = false;