Fix hygiene in top-level bindings of synthetic identifiers.

Make such bindings globally unique by creating them with uninterned
symbols, bypassing the alpha renaming which was making them look
prettier at the expense of global uniqueness.

diff --git a/src/runtime/syntax-output.scm b/src/runtime/syntax-output.scm
index 7ecbc334738e299cf306bca7c2646c0cbd87d402..c3ba6001316ac4de8d8683ec625e3b37d68381ee 100644 (file)
--- a/src/runtime/syntax-output.scm
+++ b/src/runtime/syntax-output.scm
@@ -424,7 +424,19 @@ USA.
 (define (rename-top-level-identifier identifier)
   (if (symbol? identifier)
       identifier
-      (rename-identifier identifier (delay 0))))
+      ;; Generate an uninterned symbol here and now, rather than
+      ;; storing anything in the rename database, because we are
+      ;; creating a top-level binding for a synthetic name, which must
+      ;; be globally unique.  Using the rename database causes the
+      ;; substitution logic above to try to use an interned symbol
+      ;; with a nicer name.  The decorations on this name are just
+      ;; that -- decorations, for human legibility.  It is the use of
+      ;; an uninterned symbol that guarantees uniqueness.
+      (utf8-string->uninterned-symbol
+       (string-append "."
+                     (symbol-name (identifier->symbol identifier))
+                     "."
+                     (number->string (force (make-rename-id)))))))
 
 (define (make-name-generator)
   (let ((id (make-rename-id)))