Index: gimple-fold.c
===================================================================
--- gimple-fold.c	(revision 161389)
+++ gimple-fold.c	(working copy)
@@ -1065,6 +1065,7 @@ gimplify_and_update_call_from_tree (gimp
   gimple_seq stmts = gimple_seq_alloc();
   struct gimplify_ctx gctx;
   gimple last = NULL;
+  gimple laststore = NULL;
 
   stmt = gsi_stmt (*si_p);
 
@@ -1096,12 +1097,28 @@ gimplify_and_update_call_from_tree (gimp
       find_new_referenced_vars (new_stmt);
       mark_symbols_for_renaming (new_stmt);
       last = new_stmt;
+      if (gimple_assign_single_p (last)
+	  && !is_gimple_reg (gimple_assign_lhs (last)))
+	laststore = last;
     }
 
   if (lhs == NULL_TREE)
     {
-      unlink_stmt_vdef (stmt);
-      release_defs (stmt);
+      /* If we replace a call without LHS that has a VDEF and our new
+         sequence ends with a store we must make that store have the same
+	 vdef in order not to break the sequencing.  This can happen
+	 for instance when folding memcpy calls into assignments.  */
+      if (gimple_vdef (stmt) && laststore)
+	{
+	  gimple_set_vuse (laststore, gimple_vuse (stmt));
+	  gimple_set_vdef (laststore, gimple_vdef (stmt));
+	  move_ssa_defining_stmt_for_defs (laststore, stmt);
+	}
+      else
+	{
+	  unlink_stmt_vdef (stmt);
+	  release_defs (stmt);
+	}
       new_stmt = last;
     }
   else
Index: testsuite/gfortran.dg/pr44592.f90
===================================================================
--- testsuite/gfortran.dg/pr44592.f90	(revision 0)
+++ testsuite/gfortran.dg/pr44592.f90	(revision 0)
@@ -0,0 +1,20 @@
+! { dg-do run }
+! { dg-options "-O3" }
+! From forall_12.f90
+! Fails with loop reversal at -O3
+!
+  character(len=1) :: b(4) = (/"1","2","3","4"/), c(4)
+  c = b
+  i = 1
+  ! This statement must be here for the abort below
+  b(1:3)(i:i) = b(2:4)(i:i)
+
+  b = c
+  b(4:2:-1)(i:i) = b(3:1:-1)(i:i)
+
+  ! This fails.  If the condition is printed, the result is F F F F
+  if (any (b .ne. (/"1","1","2","3"/))) i = 2
+  print *, b
+  print *, b .ne. (/"1","1","2","3"/)
+  if (i == 2) call abort
+end