Gold: Patch linker to fix LTO related bugs.

third_party/binutils/plugin-dso-fix.patch

Index: third_party/binutils/plugin-dso-fix.patch
diff --git a/third_party/binutils/plugin-dso-fix.patch b/third_party/binutils/plugin-dso-fix.patch
new file mode 100644
index 0000000000000000000000000000000000000000..558975686dce55a65cb43faca3bb2e8d5481d602
--- /dev/null
+++ b/third_party/binutils/plugin-dso-fix.patch
@@ -0,0 +1,97 @@
+commit 3c537f7fdb11f02f7082749f3f21dfdd2c2025e8
+Author: Peter Collingbourne <pcc@google.com>
+Date:   Wed Feb 4 09:47:28 2015 -0800
+
+    Resolve forwarding symbols in plugins.
+    
+    2015-02-04  Peter Collingbourne  <pcc@google.com>
+    
+    	* plugin.cc (Pluginobj::get_symbol_resolution_info): Resolve
+    	forwarding symbols when computing symbol resolution info for plugins.
+
+diff --git a/gold/plugin.cc b/gold/plugin.cc
+index bde8c78..68da8e3 100644
+--- a/gold/plugin.cc
++++ b/gold/plugin.cc
+@@ -914,7 +914,8 @@ is_visible_from_outside(Symbol* lsym)
+ // Get symbol resolution info.
+ 
+ ld_plugin_status
+-Pluginobj::get_symbol_resolution_info(int nsyms,
++Pluginobj::get_symbol_resolution_info(Symbol_table* symtab,
++				      int nsyms,
+ 				      ld_plugin_symbol* syms,
+ 				      int version) const
+ {
+@@ -943,6 +944,8 @@ Pluginobj::get_symbol_resolution_info(int nsyms,
+     {
+       ld_plugin_symbol* isym = &syms[i];
+       Symbol* lsym = this->symbols_[i];
++      if (lsym->is_forwarder())
++        lsym = symtab->resolve_forwards(lsym);
+       ld_plugin_symbol_resolution res = LDPR_UNKNOWN;
+ 
+       if (lsym->is_undefined())
+@@ -1511,14 +1514,16 @@ static enum ld_plugin_status
+ get_symbols(const void* handle, int nsyms, ld_plugin_symbol* syms)
+ {
+   gold_assert(parameters->options().has_plugins());
+-  Object* obj = parameters->options().plugins()->object(
++  Plugin_manager* plugins = parameters->options().plugins();
++  Object* obj = plugins->object(
+     static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)));
+   if (obj == NULL)
+     return LDPS_ERR;
+   Pluginobj* plugin_obj = obj->pluginobj();
+   if (plugin_obj == NULL)
+     return LDPS_ERR;
+-  return plugin_obj->get_symbol_resolution_info(nsyms, syms, 1);
++  Symbol_table* symtab = plugins->symtab();
++  return plugin_obj->get_symbol_resolution_info(symtab, nsyms, syms, 1);
+ }
+ 
+ // Version 2 of the above.  The only difference is that this version
+@@ -1528,14 +1533,16 @@ static enum ld_plugin_status
+ get_symbols_v2(const void* handle, int nsyms, ld_plugin_symbol* syms)
+ {
+   gold_assert(parameters->options().has_plugins());
+-  Object* obj = parameters->options().plugins()->object(
++  Plugin_manager* plugins = parameters->options().plugins();
++  Object* obj = plugins->object(
+     static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)));
+   if (obj == NULL)
+     return LDPS_ERR;
+   Pluginobj* plugin_obj = obj->pluginobj();
+   if (plugin_obj == NULL)
+     return LDPS_ERR;
+-  return plugin_obj->get_symbol_resolution_info(nsyms, syms, 2);
++  Symbol_table* symtab = plugins->symtab();
++  return plugin_obj->get_symbol_resolution_info(symtab, nsyms, syms, 2);
+ }
+ 
+ // Add a new (real) input file generated by a plugin.
+diff --git a/gold/plugin.h b/gold/plugin.h
+index ef78b84..f926879 100644
+--- a/gold/plugin.h
++++ b/gold/plugin.h
+@@ -282,6 +282,10 @@ class Plugin_manager
+   input_objects() const
+   { return this->input_objects_; }
+ 
++  Symbol_table*
++  symtab()
++  { return this->symtab_; }
++
+   Layout*
+   layout()
+   { return this->layout_; }
+@@ -396,7 +400,8 @@ class Pluginobj : public Object
+ 
+   // Fill in the symbol resolution status for the given plugin symbols.
+   ld_plugin_status
+-  get_symbol_resolution_info(int nsyms,
++  get_symbol_resolution_info(Symbol_table* symtab,
++			     int nsyms,
+ 			     ld_plugin_symbol* syms,
+ 			     int version) const;
+