re PR middle-end/53708 (Many failures of the objc tests with -O3 -fnext-runtime and -m32)

2012-10-31  Jakub Jelinek  <jakub@redhat.com>

	PR tree-optimization/53708
	* tree-vect-data-refs.c (vect_can_force_dr_alignment_p): Preserve
	user-supplied alignment when used with an explicit section name.

From-SVN: r193058

gcc/ChangeLog

+2012-10-31  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/53708
+	* tree-vect-data-refs.c (vect_can_force_dr_alignment_p): Preserve
+	user-supplied alignment when used with an explicit section name.
+
 2012-10-31  Dehao Chen  <dehao@google.com>
 
 	* tree-eh.c (do_return_redirection): Set location for jump statement.

gcc/tree-vect-data-refs.c

@@ -4858,6 +4858,13 @@ vect_can_force_dr_alignment_p (const_tree decl, unsigned int alignment)
   if (DECL_PRESERVE_P (decl))
     return false;
 
+  /* Do not override explicit alignment set by the user when an explicit
+     section name is also used.  This is a common idiom used by many
+     software projects.  */
+  if (DECL_SECTION_NAME (decl) != NULL_TREE
+      && !DECL_HAS_IMPLICIT_SECTION_NAME_P (decl))
+    return false;
+
   if (TREE_STATIC (decl))
     return (alignment <= MAX_OFILE_ALIGNMENT);
   else