llvm-project/flang/test/Preprocessing/pp045.F

! RUN: %flang -E %s 2>&1 | FileCheck %s
! CHECK: n = "foobar" // "baz"
* # stringizing works in FLM
#define STR(x) # x
#define MAC(a,b) STR(a ## b)
      program main
      character(6) n
      n = MAC(foo, bar) // STR( baz )
      end