test/Modules/Inputs/merge-decl-context/merge-decl-context.modulemap

module "a" {
  textual header "a.h"
}

module "b" {
  export *
  header "b.h"
}

module "c" {
  export *
  header "c.h"
}

module "d" {
  export *
  header "d.h"
}