diff --git a/module/mescc/M1.scm b/module/mescc/M1.scm
index 790ef881..56a79d08 100644
--- a/module/mescc/M1.scm
+++ b/module/mescc/M1.scm
@@ -88,16 +88,13 @@
   (if hex? (string-append "%0x" (dec->hex o))
       (string-append "%" (number->string o))))
 
-(define mesc? (string=? %compiler "mesc"))
-
 (define (hex2:immediate8 o)
-  ;; FIXME: #x100000000 => 0 divide-by-zero when compiled with 64 bit mesc
-  (if hex? (string-append "%0x" (dec->hex (if mesc? 0 (modulo o #x100000000)))
+  (if hex? (string-append "%0x" (dec->hex (modulo o #x100000000))
                           " %0x" (if (< o 0) "-1"
-                                     (dec->hex (if mesc? o (quotient o #x100000000)))))
-      (string-append "%" (number->string (dec->hex (if mesc? 0 (modulo o #x100000000))))
+                                     (dec->hex (quotient o #x100000000))))
+      (string-append "%" (number->string (dec->hex (modulo o #x100000000)))
                      " %" (if (< o 0) "-1"
-                              (number->string (dec->hex (if mesc? o (quotient o #x100000000))))))))
+                              (number->string (dec->hex (quotient o #x100000000)))))))
 
 (define* (display-join o #:optional (sep ""))
   (let loop ((o o))