PR24144, pdp11-ld overwriting section data with zeros

bfd/
	PR 24144
	* pdp11.c (set_section_contents): Revert 2015-02-24 change.
gas/
	PR 24144
	* config/obj-aout.c (obj_aout_frob_file_before_fix): Write to end
	of section to ensure file contents cover aligned section size.

2 files changed, 27 insertions, 11 deletions

diff --git a/gas/ChangeLog b/gas/ChangeLog
index a301c04..03c9b4e 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,9 @@
+2019-02-24  Alan Modra  <amodra@gmail.com>
+
+	PR 24144
+	* config/obj-aout.c (obj_aout_frob_file_before_fix): Write to end
+	of section to ensure file contents cover aligned section size.
+
 2019-02-22  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
 
 	* config/tc-arm.c (arm_cpus): Add neoverse-n1.
diff --git a/gas/config/obj-aout.c b/gas/config/obj-aout.c
index 22e103b..03e0ef3 100644
--- a/gas/config/obj-aout.c
+++ b/gas/config/obj-aout.c
@@ -118,17 +118,27 @@ obj_aout_frob_file_before_fix (void)
 {
   /* Relocation processing may require knowing the VMAs of the sections.
      Since writing to a section will cause the BFD back end to compute the
-     VMAs, fake it out here....  */
-  bfd_byte b = 0;
-  bfd_boolean x = TRUE;
-  if (bfd_section_size (stdoutput, text_section) != 0)
-    x = bfd_set_section_contents (stdoutput, text_section, &b, (file_ptr) 0,
-				  (bfd_size_type) 1);
-  else if (bfd_section_size (stdoutput, data_section) != 0)
-    x = bfd_set_section_contents (stdoutput, data_section, &b, (file_ptr) 0,
-				  (bfd_size_type) 1);
-
-  gas_assert (x);
+     VMAs, fake it out here....
+     Writing to the end of the section ensures the file contents
+     extend to cover the entire aligned size.  We possibly won't know
+     the aligned size until after VMAs and sizes are set on the first
+     bfd_set_section_contents call, so it might be necessary to repeat.  */
+  asection *sec = NULL;
+  if (data_section->size != 0)
+    sec = data_section;
+  else if (text_section->size != 0)
+    sec = text_section;
+  if (sec)
+    {
+      bfd_size_type size;
+      do
+	{
+	  bfd_byte b = 0;
+	  size = sec->size;
+	  gas_assert (bfd_set_section_contents (stdoutput, sec, &b,
+						size - 1, (bfd_size_type) 1));
+	} while (size != sec->size);
+    }
 }
 
 static void