diff --git a/prometheus/process_collector_procfs.go b/prometheus/process_collector_procfs.go
index 5a09ded..b291d2b 100644
--- a/prometheus/process_collector_procfs.go
+++ b/prometheus/process_collector_procfs.go
@@ -11,8 +11,6 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// +build linux,cgo plan9,cgo solaris,cgo
-
 package prometheus
 
 import "github.com/prometheus/procfs"
diff --git a/prometheus/process_collector_rest.go b/prometheus/process_collector_rest.go
deleted file mode 100644
index 0b3698a..0000000
--- a/prometheus/process_collector_rest.go
+++ /dev/null
@@ -1,24 +0,0 @@
-// Copyright 2015 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// +build !linux,!plan9,!solaris !cgo
-
-package prometheus
-
-func processCollectSupported() bool {
-	return false
-}
-
-func (c *processCollector) processCollect(ch chan<- Metric) {
-	panic("unreachable")
-}