diff --git a/gcc/fortran/trans-expr.cc b/gcc/fortran/trans-expr.cc
index ab710efc451..d7a368a685f 100644
--- a/gcc/fortran/trans-expr.cc
+++ b/gcc/fortran/trans-expr.cc
@@ -8093,6 +8093,13 @@ gfc_trans_string_copy (stmtblock_t * block, tree dlength, tree dest,
   cond2 = fold_build2_loc (input_location, LT_EXPR, logical_type_node, slen,
 			   dlen);
 
+  /* Pre-evaluate pointers unless one of the IF arms will be optimized away.  */
+  if (!CONSTANT_CLASS_P (cond2))
+    {
+      dest = gfc_evaluate_now (dest, block);
+      src = gfc_evaluate_now (src, block);
+    }
+
   /* Copy and pad with spaces.  */
   tmp3 = build_call_expr_loc (input_location,
 			      builtin_decl_explicit (BUILT_IN_MEMMOVE),
diff --git a/gcc/testsuite/gfortran.dg/dependency_49.f90 b/gcc/testsuite/gfortran.dg/dependency_49.f90
index 73d517e8f76..9638f65c069 100644
--- a/gcc/testsuite/gfortran.dg/dependency_49.f90
+++ b/gcc/testsuite/gfortran.dg/dependency_49.f90
@@ -11,4 +11,5 @@ program main
   a%x = a%x(2:3)
   print *,a%x
 end program main
-! { dg-final { scan-tree-dump-times "__var_1" 4 "original" } }
+! The temporary var appears three times: declaration, copy-in and copy-out
+! { dg-final { scan-tree-dump-times "__var_1" 3 "original" } }