diff --git a/src/runtime/gengoos.go b/src/runtime/gengoos.go
index 029575bee22..06621c8dba2 100644
--- a/src/runtime/gengoos.go
+++ b/src/runtime/gengoos.go
@@ -46,7 +46,9 @@ func main() {
 	for _, target := range gooses {
 		var buf bytes.Buffer
 		fmt.Fprintf(&buf, "// generated by gengoos.go using 'go generate'\n\n")
-		fmt.Fprintf(&buf, "// +build %s\n\n", target) // usually redundant, but not always; see linux vs android
+		if target == "linux" {
+			fmt.Fprintf(&buf, "// +build !android\n\n") // must explicitly exclude android for linux
+		}
 		fmt.Fprintf(&buf, "package runtime\n\n")
 		fmt.Fprintf(&buf, "const theGoos = `%s`\n\n", target)
 		for _, goos := range gooses {
diff --git a/src/runtime/zgoos_android.go b/src/runtime/zgoos_android.go
index abfba808ba5..0590bd9ab7d 100644
--- a/src/runtime/zgoos_android.go
+++ b/src/runtime/zgoos_android.go
@@ -1,7 +1,5 @@
 // generated by gengoos.go using 'go generate'
 
-// +build android
-
 package runtime
 
 const theGoos = `android`
diff --git a/src/runtime/zgoos_darwin.go b/src/runtime/zgoos_darwin.go
index eb39b53dd46..c0a7cd6e747 100644
--- a/src/runtime/zgoos_darwin.go
+++ b/src/runtime/zgoos_darwin.go
@@ -1,7 +1,5 @@
 // generated by gengoos.go using 'go generate'
 
-// +build darwin
-
 package runtime
 
 const theGoos = `darwin`
diff --git a/src/runtime/zgoos_dragonfly.go b/src/runtime/zgoos_dragonfly.go
index f6e839d3d83..008d6de8118 100644
--- a/src/runtime/zgoos_dragonfly.go
+++ b/src/runtime/zgoos_dragonfly.go
@@ -1,7 +1,5 @@
 // generated by gengoos.go using 'go generate'
 
-// +build dragonfly
-
 package runtime
 
 const theGoos = `dragonfly`
diff --git a/src/runtime/zgoos_freebsd.go b/src/runtime/zgoos_freebsd.go
index 3c47aef2ab4..2478940353e 100644
--- a/src/runtime/zgoos_freebsd.go
+++ b/src/runtime/zgoos_freebsd.go
@@ -1,7 +1,5 @@
 // generated by gengoos.go using 'go generate'
 
-// +build freebsd
-
 package runtime
 
 const theGoos = `freebsd`
diff --git a/src/runtime/zgoos_linux.go b/src/runtime/zgoos_linux.go
index 5d899e3db6c..c775ab538d4 100644
--- a/src/runtime/zgoos_linux.go
+++ b/src/runtime/zgoos_linux.go
@@ -1,6 +1,6 @@
 // generated by gengoos.go using 'go generate'
 
-// +build linux
+// +build !android
 
 package runtime
 
diff --git a/src/runtime/zgoos_nacl.go b/src/runtime/zgoos_nacl.go
index b5c4281fb56..d9d88f4508a 100644
--- a/src/runtime/zgoos_nacl.go
+++ b/src/runtime/zgoos_nacl.go
@@ -1,7 +1,5 @@
 // generated by gengoos.go using 'go generate'
 
-// +build nacl
-
 package runtime
 
 const theGoos = `nacl`
diff --git a/src/runtime/zgoos_netbsd.go b/src/runtime/zgoos_netbsd.go
index b2e45222ae3..ff2c5cb8f4a 100644
--- a/src/runtime/zgoos_netbsd.go
+++ b/src/runtime/zgoos_netbsd.go
@@ -1,7 +1,5 @@
 // generated by gengoos.go using 'go generate'
 
-// +build netbsd
-
 package runtime
 
 const theGoos = `netbsd`
diff --git a/src/runtime/zgoos_openbsd.go b/src/runtime/zgoos_openbsd.go
index 331c96dd662..b071dc63ab7 100644
--- a/src/runtime/zgoos_openbsd.go
+++ b/src/runtime/zgoos_openbsd.go
@@ -1,7 +1,5 @@
 // generated by gengoos.go using 'go generate'
 
-// +build openbsd
-
 package runtime
 
 const theGoos = `openbsd`
diff --git a/src/runtime/zgoos_plan9.go b/src/runtime/zgoos_plan9.go
index f29eb452304..4306b0f1ef4 100644
--- a/src/runtime/zgoos_plan9.go
+++ b/src/runtime/zgoos_plan9.go
@@ -1,7 +1,5 @@
 // generated by gengoos.go using 'go generate'
 
-// +build plan9
-
 package runtime
 
 const theGoos = `plan9`
diff --git a/src/runtime/zgoos_solaris.go b/src/runtime/zgoos_solaris.go
index ac613db33c4..10f9537d05b 100644
--- a/src/runtime/zgoos_solaris.go
+++ b/src/runtime/zgoos_solaris.go
@@ -1,7 +1,5 @@
 // generated by gengoos.go using 'go generate'
 
-// +build solaris
-
 package runtime
 
 const theGoos = `solaris`
diff --git a/src/runtime/zgoos_windows.go b/src/runtime/zgoos_windows.go
index 43710d862fe..56f5c58ce64 100644
--- a/src/runtime/zgoos_windows.go
+++ b/src/runtime/zgoos_windows.go
@@ -1,7 +1,5 @@
 // generated by gengoos.go using 'go generate'
 
-// +build windows
-
 package runtime
 
 const theGoos = `windows`