build: separate compiler and libs

cl/_testdefer/firstloop1/in.go

@@ -1,16 +0,0 @@
-package foo
-
-func f(s string) bool {
-	return len(s) > 2
-}
-
-func Loop() {
-	for i := 0; i < 3; i++ {
-		if s := "hello"; f(s) {
-			defer println(s)
-		} else {
-			defer println("world")
-			return
-		}
-	}
-}

cl/_testdefer/firstloop1/out.txt

@@ -1,7 +0,0 @@
- 0: always
- 6: cond
- 1: loop
- 2: loop
- 4: loop
- 3: cond
- 5: cond