Allow zero length archive elements.

bfd	PR binutils/19775
	* archive.c (bfd_generic_openr_next_archived_file): Allow zero
	length elements in the archive.

binutils PR binutils/19775
	* testsuite/binutils-all/ar.exp (proc empty_archive): New proc.
	Run the new proc.
	* testsuite/binutils-all/empty: New, empty, file.

bfd/ChangeLog

@@ -1,3 +1,9 @@
+2016-03-07  Nick Clifton  <nickc@redhat.com>
+
+	PR binutils/19775
+	* archive.c (bfd_generic_openr_next_archived_file): Allow zero
+	length elements in the archive.
+
 2016-03-07  Jiong Wang  <jiong.wang@arm.com>
 
 	* elfnn-aarch64.c (elfNN_aarch64_check_relocs): Always create .got

bfd/archive.c

@@ -802,7 +802,7 @@ bfd_generic_openr_next_archived_file (bfd *archive, bfd *last_file)
 	     Note that last_file->origin can be odd in the case of
 	     BSD-4.4-style element with a long odd size.  */
 	  filestart += filestart % 2;
-	  if (filestart <= last_file->proxy_origin)
+	  if (filestart < last_file->proxy_origin)
 	    {
 	      /* Prevent looping.  See PR19256.  */
 	      bfd_set_error (bfd_error_malformed_archive);

binutils/ChangeLog

@@ -1,3 +1,10 @@
+2016-03-07  Nick Clifton  <nickc@redhat.com>
+
+	PR binutils/19775
+	* testsuite/binutils-all/ar.exp (proc empty_archive): New proc.
+	Run the new proc.
+	* testsuite/binutils-all/empty: New, empty, file.
+
 2016-03-04  Matthew Wahab  <matthew.wahab@arm.com>
 
 	* readelf.c (arm_attry_tag_FP_arch): Add "NEON for ARMv8.1".

binutils/testsuite/binutils-all/ar.exp

@@ -555,6 +555,45 @@ proc move_an_element { } {
     pass $testname
 }
 
+# PR 19775: Test creating and listing archives with an empty element.
+
+proc empty_archive { } {
+    global AR
+    global srcdir
+    global subdir
+
+    set testname "archive with empty element"
+
+    # FIXME: There ought to be a way to dynamically create an empty file.
+    set empty $srcdir/$subdir/empty
+    
+    if [is_remote host] {
+	set archive artest.a
+	set objfile [remote_download host $empty]
+	remote_file host delete $archive
+    } else {
+	set archive tmpdir/artest.a
+	set objfile $empty
+    }
+
+    remote_file build delete tmpdir/artest.a
+
+    set got [binutils_run $AR "-r -c $archive ${objfile}"]
+    if ![string match "" $got] {
+	fail $testname
+	return
+    }
+
+    # This commmand used to fail with: "Malformed archive".
+    set got [binutils_run $AR "-t $archive"]
+    if ![string match "empty
" $got] {
+	fail $testname
+	return
+    }
+
+    pass $testname
+}
+
 # Run the tests.
 
 # Only run the bfdtest checks if the programs exist.  Since these
@@ -574,6 +613,7 @@ argument_parsing
 deterministic_archive
 delete_an_element
 move_an_element
+empty_archive
 
 if { [is_elf_format]
      && ![istarget "*-*-hpux*"]