1 files changed, 45 insertions, 0 deletions
diff --git a/gcc/testsuite/gfortran.dg/der_io_3.f90 b/gcc/testsuite/gfortran.dg/der_io_3.f90
new file mode 100644
index 000000000..1cb370ce1
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/der_io_3.f90
@@ -0,0 +1,45 @@
+! { dg-do compile }
+! { dg-options "-std=legacy" }
+!
+! PR23843
+! Make sure derived type I/O with PRIVATE components works where it's allowed
+module m1
+  type t1
+     integer i
+  end type t1
+end module m1
+
+module m2
+  use m1
+
+  type t2
+     private
+     type (t1) t
+  end type t2
+
+  type t3
+     private
+     integer i
+  end type t3
+
+contains
+  subroutine test
+    character*20 c
+    type(t2) :: a
+    type(t3) :: b
+
+    a % t % i = 31337
+    b % i = 255
+    
+    write(c,*) a
+    if (trim(adjustl(c)) /= "31337") call abort
+    write(c,*) b
+    if (trim(adjustl(c)) /= "255") call abort
+  end subroutine test
+end module m2
+
+use m2
+call test
+end
+
+! { dg-final { cleanup-modules "m1 m2" } }