diff --git a/gold/ChangeLog b/gold/ChangeLog
index 8ec7014b2a9..37643cca01b 100644
--- a/gold/ChangeLog
+++ b/gold/ChangeLog
@@ -1,3 +1,10 @@
+2019-09-20  Alan Modra  <amodra@gmail.com>
+
+	PR 24768
+	* layout.cc (Layout::Layout): Init lto_slim_object_.
+	* object.cc (Sized_relobj_file::do_layout): Wrap overlong line.
+	Don't use C cast.  Validate section size.  Don't copy contents.
+
 2019-09-20  Alan Modra  <amodra@gmail.com>
 
 	* powerpc.cc (Target_powerpc::Scan::check_non_pic): Move REL24
diff --git a/gold/layout.cc b/gold/layout.cc
index fc7cdf8b8bb..194d088c2a1 100644
--- a/gold/layout.cc
+++ b/gold/layout.cc
@@ -466,6 +466,7 @@ Layout::Layout(int number_of_input_files, Script_options* script_options)
     unique_segment_for_sections_specified_(false),
     incremental_inputs_(NULL),
     record_output_section_data_from_script_(false),
+    lto_slim_object_(false),
     script_output_section_data_list_(),
     segment_states_(NULL),
     relaxation_debug_check_(NULL),
diff --git a/gold/object.cc b/gold/object.cc
index d505ce47520..2fca7eb2278 100644
--- a/gold/object.cc
+++ b/gold/object.cc
@@ -1884,10 +1884,15 @@ Sized_relobj_file<size, big_endian>::do_layout(Symbol_table* symtab,
       if (strncmp (name, lto_section_name, strlen (lto_section_name)) == 0)
 	{
 	  section_size_type contents_len;
-	  const unsigned char* pcontents = this->section_contents(i, &contents_len, false);
-	  struct lto_section lsection = *(const lto_section*)pcontents;
-	  if (lsection.slim_object)
-	    layout->set_lto_slim_object ();
+	  const unsigned char* pcontents
+	    = this->section_contents(i, &contents_len, false);
+	  if (contents_len >= sizeof(lto_section))
+	    {
+	      const lto_section* lsection
+		= reinterpret_cast<const lto_section*>(pcontents);
+	      if (lsection->slim_object)
+		layout->set_lto_slim_object();
+	    }
 	}
     }