2008-04-04 Cary Coutant <ccoutant@google.com>

	* symtab.h (Symbol::is_weak_undefined): New function.
	(Symbol::is_strong_undefined): New function.
	(Symbol::is_absolute): New function.
	(Symbol::needs_plt_entry): Exclude weak undefined symbols.
	(Symbol::needs_dynamic_reloc): Exclude weak undefined and
	absolute symbols.
	* testsuite/Makefile.am (check_PROGRAMS): Add weak_undef_test.
	(weak_undef_test): New target.
	* testsuite/Makefile.in: Rebuild.
	* testsuite/weak_undef_file1.cc: New file.
	* testsuite/weak_undef_file2.cc: New file.
	* testsuite/weak_undef_test.cc: New file.

1 files changed, 31 insertions, 1 deletions

diff --git a/gold/symtab.h b/gold/symtab.h
index bd41794..e262cd4 100644
--- a/gold/symtab.h
+++ b/gold/symtab.h
@@ -405,6 +405,31 @@ class Symbol
     return this->source_ == FROM_OBJECT && this->shndx() == elfcpp::SHN_UNDEF;
   }
 
+  // Return whether this is a weak undefined symbol.
+  bool
+  is_weak_undefined() const
+  {
+    return (this->source_ == FROM_OBJECT
+            && this->binding() == elfcpp::STB_WEAK
+            && this->shndx() == elfcpp::SHN_UNDEF);
+  }
+
+  // Return whether this is a strong (i.e., not weak) undefined symbol.
+  bool
+  is_strong_undefined() const
+  {
+    return (this->source_ == FROM_OBJECT
+            && this->binding() != elfcpp::STB_WEAK
+            && this->shndx() == elfcpp::SHN_UNDEF);
+  }
+
+  // Return whether this is an absolute symbol.
+  bool
+  is_absolute() const
+  {
+    return this->source_ == FROM_OBJECT && this->shndx() == elfcpp::SHN_ABS;
+  }
+
   // Return whether this is a common symbol.
   bool
   is_common() const
@@ -453,7 +478,7 @@ class Symbol
     return (!parameters->doing_static_link()
             && this->type() == elfcpp::STT_FUNC
             && (this->is_from_dynobj()
-                || this->is_undefined()
+                || this->is_strong_undefined()
                 || this->is_preemptible()));
   }
 
@@ -481,6 +506,11 @@ class Symbol
     if (parameters->doing_static_link())
       return false;
 
+    // A reference to a weak undefined symbol or to an absolute symbol
+    // does not need a dynamic relocation.
+    if (this->is_weak_undefined() || this->is_absolute())
+      return false;
+
     // An absolute reference within a position-independent output file
     // will need a dynamic relocation.
     if ((flags & ABSOLUTE_REF)