Fix problem where -u is ignored when a weak undef is seen.

When the linker has a weak undefined symbol, it normally does not
select an archive library member just to satisfy the reference.
If the same symbol is also listed in a -u option, however, we
should select the archive library member.  This patch reorders
the code in Library_base::should_include_member so that the
additional checks are performed in the case of a weak undef.

gold/

2014-02-06  Cary Coutant  <ccoutant@google.com>

	* archive.cc (Library_base::should_include_member): Reorder
	code to check for -u option if a weak undef has already been seen.
	* testsuite/Makefile.am (weak_undef_test_2): New test case.
	* testsuite/Makefile.in: Regenerate.
	* testsuite/weak_undef_file3.cc: New file.
	* testsuite/weak_undef_file4.cc: New file.
	* testsuite/weak_undef_test_2.cc: New file.

1 files changed, 48 insertions, 38 deletions

diff --git a/gold/archive.cc b/gold/archive.cc
index 53d88a2..b52ebd3 100644
--- a/gold/archive.cc
+++ b/gold/archive.cc
@@ -97,46 +97,56 @@ Library_base::should_include_member(Symbol_table* symtab, Layout* layout,
 
   *symp = sym;
 
-  if (sym == NULL)
+  if (sym != NULL)
     {
-      // Check whether the symbol was named in a -u option.
-      if (parameters->options().is_undefined(sym_name))
-        {
-          *why = "-u ";
-          *why += sym_name;
-        }
-      else if (parameters->options().is_export_dynamic_symbol(sym_name))
-        {
-          *why = "--export-dynamic-symbol ";
-          *why += sym_name;
-        }
-      else if (layout->script_options()->is_referenced(sym_name))
-	{
-	  size_t alc = 100 + strlen(sym_name);
-	  char* buf = new char[alc];
-	  snprintf(buf, alc, _("script or expression reference to %s"),
-		   sym_name);
-	  *why = buf;
-	  delete[] buf;
-	}
-      else if (strcmp(sym_name, parameters->entry()) == 0)
-	{
-	  *why = "entry symbol ";
-	  *why += sym_name;
-	}
-      else
-	return Library_base::SHOULD_INCLUDE_UNKNOWN;
+      if (!sym->is_undefined())
+	return Library_base::SHOULD_INCLUDE_NO;
+
+      // PR 12001: Do not include an archive when the undefined
+      // symbol has actually been defined on the command line.
+      if (layout->script_options()->is_pending_assignment(sym_name))
+	return Library_base::SHOULD_INCLUDE_NO;
+
+      // If the symbol is weak undefined, we still need to check
+      // for other reasons (like a -u option).
+      if (sym->binding() != elfcpp::STB_WEAK)
+	return Library_base::SHOULD_INCLUDE_YES;
+    }
+
+  // Check whether the symbol was named in a -u option.
+  if (parameters->options().is_undefined(sym_name))
+    {
+      *why = "-u ";
+      *why += sym_name;
+      return Library_base::SHOULD_INCLUDE_YES;
+    }
+
+  if (parameters->options().is_export_dynamic_symbol(sym_name))
+    {
+      *why = "--export-dynamic-symbol ";
+      *why += sym_name;
+      return Library_base::SHOULD_INCLUDE_YES;
     }
-  else if (!sym->is_undefined())
-    return Library_base::SHOULD_INCLUDE_NO;
-  // PR 12001: Do not include an archive when the undefined
-  // symbol has actually been defined on the command line.
-  else if (layout->script_options()->is_pending_assignment(sym_name))
-    return Library_base::SHOULD_INCLUDE_NO;
-  else if (sym->binding() == elfcpp::STB_WEAK)
-    return Library_base::SHOULD_INCLUDE_UNKNOWN;
-
-  return Library_base::SHOULD_INCLUDE_YES;
+
+  if (layout->script_options()->is_referenced(sym_name))
+    {
+      size_t alc = 100 + strlen(sym_name);
+      char* buf = new char[alc];
+      snprintf(buf, alc, _("script or expression reference to %s"),
+	       sym_name);
+      *why = buf;
+      delete[] buf;
+      return Library_base::SHOULD_INCLUDE_YES;
+    }
+
+  if (strcmp(sym_name, parameters->entry()) == 0)
+    {
+      *why = "entry symbol ";
+      *why += sym_name;
+      return Library_base::SHOULD_INCLUDE_YES;
+    }
+
+  return Library_base::SHOULD_INCLUDE_UNKNOWN;
 }
 
 // The header of an entry in the archive.  This is all readable text,