Don't export write-bytecode' from (language assembly compile-bytecode)'.

* module/language/assembly/compile-bytecode.scm: Don't export
  `write-bytecode'.

* test-suite/tests/asm-to-bytecode.test (write-bytecode): New global
  variable.

module/language/assembly/compile-bytecode.scm

@@ -27,7 +27,7 @@
   #:use-module (rnrs io ports)
   #:use-module ((srfi srfi-1) #:select (fold))
   #:use-module ((srfi srfi-26) #:select (cut))
-  #:export (compile-bytecode write-bytecode))
+  #:export (compile-bytecode))
 
 (define (compile-bytecode assembly env . opts)
   (pmatch assembly

test-suite/tests/asm-to-bytecode.test

@@ -21,6 +21,9 @@
   #:use-module (system vm instruction)
   #:use-module (language assembly compile-bytecode))
 
+(define write-bytecode
+  (@@ (language assembly compile-bytecode) write-bytecode))
+
 (define (->u8-list sym val)
   (let ((entry (assq-ref `((uint16 2 ,bytevector-u16-native-set!)
                            (uint32 4 ,bytevector-u32-native-set!))