--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/gfortran.dg/public_private_module_8.f90	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,49 @@
+! { dg-do compile }
+! { dg-options "-O2" }
+!
+! PR fortran/54884
+!
+! Check that get_key_len is not optimized away as it
+! is used in a publicly visible specification expression.
+!
+
+module m
+  private
+  public :: foo
+  interface foo
+    module procedure bar
+  end interface foo
+contains
+  pure function mylen()
+    integer :: mylen
+    mylen = 42
+  end function mylen
+  pure function myotherlen()
+    integer :: myotherlen
+    myotherlen = 99
+  end function myotherlen
+  subroutine bar(x)
+    character(len=mylen()) :: x
+    character :: z2(myotherlen())
+    call internal(x)
+    block
+       character(len=myotherlen()) :: z
+       z = "abc"
+       x(1:5) = z
+    end block
+    x(6:10) = intern_func()
+  contains
+    function intern_func()
+      character(len=myotherlen()) :: intern_func
+      intern_func = "zuzu"
+    end function intern_func
+   subroutine internal(y)
+      character(len=myotherlen()) :: y
+      y = "abc"
+    end subroutine internal
+  end subroutine bar
+end module m
+
+! { dg-final { scan-assembler-not "__m_MOD_myotherlen" } }
+! { dg-final { scan-assembler "__m_MOD_bar" } }
+! { dg-final { scan-assembler "__m_MOD_mylen" } }