From 9d17a35539ff99c966bb872823a9fc3a3f4e344b Mon Sep 17 00:00:00 2001
From: Matthew Flatt <mflatt@racket-lang.org>
Date: Wed, 30 Jul 2014 10:33:52 +0100
Subject: [PATCH] fix `expand` on a `module` containing lifts from expression

Another attempt at the bug that b95baa1d25 was intended to fix.
---
 .../racket-test/tests/racket/cross-phase.rkt  | 17 ----------
 .../racket-test/tests/racket/macro.rktl       | 31 +++++++++++++++++++
 racket/src/racket/src/module.c                | 10 ++++--
 3 files changed, 39 insertions(+), 19 deletions(-)

diff --git a/pkgs/racket-pkgs/racket-test/tests/racket/cross-phase.rkt b/pkgs/racket-pkgs/racket-test/tests/racket/cross-phase.rkt
index f10462a71e..875ced07d8 100644
--- a/pkgs/racket-pkgs/racket-test/tests/racket/cross-phase.rkt
+++ b/pkgs/racket-pkgs/racket-test/tests/racket/cross-phase.rkt
@@ -116,21 +116,4 @@
             '(module m '#%kernel
                (#%declare #:cross-phase-persistent))))))
 
-;; Check that `expand` produces valies syntax
-(let ()
-  (define e
-    (syntax->datum
-     (parameterize ([current-namespace (make-base-namespace)])
-       (expand '(module m '#%kernel
-                  (#%declare #:cross-phase-persistent))))))
-  (let loop ([e e])
-    (cond
-     [(syntax? e) (loop (syntax-e e))]
-     [(pair? e) (loop (car e)) (loop (cdr e))]
-     [(null? e) (void)]
-     [(symbol? e) (void)]
-     [(keyword? e) (void)]
-     [else (error 'expand-test "unexpected value: ~e" e)])))
-
 (displayln "All tests passed.")
-
diff --git a/pkgs/racket-pkgs/racket-test/tests/racket/macro.rktl b/pkgs/racket-pkgs/racket-test/tests/racket/macro.rktl
index 87440317a6..a2705f034a 100644
--- a/pkgs/racket-pkgs/racket-test/tests/racket/macro.rktl
+++ b/pkgs/racket-pkgs/racket-test/tests/racket/macro.rktl
@@ -1095,4 +1095,35 @@
 
 ;; ----------------------------------------
 
+;; Check that `expand` produces valied syntax
+(let ()
+  (define (check mod)
+    (define e
+      (syntax->datum
+       (parameterize ([current-namespace (make-base-namespace)])
+         (expand mod))))
+    (let loop ([e e])
+      (cond
+       [(syntax? e) (loop (syntax-e e))]
+       [(pair? e) (loop (car e)) (loop (cdr e))]
+       [(null? e) (void)]
+       [(symbol? e) (void)]
+       [(keyword? e) (void)]
+       [(number? e) (void)]
+       [(boolean? e) (void)]
+       [else (error 'expand-test "unexpected value: ~e" e)])))
+  (check '(module m '#%kernel
+            (#%declare #:cross-phase-persistent)))
+  (check '(module m '#%kernel
+            (define-values (x) 10)))
+  (check '(module m racket/base
+            (require (for-syntax racket/base))
+            (define-syntax (m stx)
+              (syntax-local-lift-expression #'(+ 1 2)))
+            (list (m))))
+  (check '(module m racket/base
+            (module+ main 10))))
+
+;; ----------------------------------------
+
 (report-errs)
diff --git a/racket/src/racket/src/module.c b/racket/src/racket/src/module.c
index b9c3bf61f0..0f8425f3f6 100644
--- a/racket/src/racket/src/module.c
+++ b/racket/src/racket/src/module.c
@@ -292,6 +292,7 @@ THREAD_LOCAL_DECL(static Scheme_Object *global_shift_cache);
 #define PROVIDE_MODFORM_KIND 3
 #define MODULE_MODFORM_KIND 4
 #define SAVED_MODFORM_KIND 5
+#define DECLARE_MODFORM_KIND 6
 
 /* combined bitwise: */
 #define NON_PHASELESS_IMPORT 0x1
@@ -9157,7 +9158,7 @@ static Scheme_Object *do_module_begin_at_phase(Scheme_Object *form, Scheme_Comp_
           if (!SCHEME_STX_NULLP(kws))
             scheme_wrong_syntax(who, NULL, e, IMPROPER_LIST_FORM);
           
-          kind = SAVED_MODFORM_KIND;
+          kind = DECLARE_MODFORM_KIND;
 	} else if (scheme_stx_module_eq_x(scheme_module_stx, fst, phase)
                    || scheme_stx_module_eq_x(scheme_modulestar_stx, fst, phase)) {
 	  /************ module[*] *************/
@@ -9312,8 +9313,13 @@ static Scheme_Object *do_module_begin_at_phase(Scheme_Object *form, Scheme_Comp_
     SCHEME_EXPAND_OBSERVE_NEXT(observer);
 
     if (kind == SAVED_MODFORM_KIND) {
-      expanded_l = scheme_make_pair(e, expanded_l);
+      expanded_l = scheme_make_pair(SCHEME_CDR(e), expanded_l);
+      SCHEME_CAR(p) = SCHEME_CAR(e);
+      prev_p = p;
       p = SCHEME_CDR(p);      
+    } else if (kind == DECLARE_MODFORM_KIND) {
+      expanded_l = scheme_make_pair(e, expanded_l);
+      p = SCHEME_CDR(p);
     } else if ((kind == PROVIDE_MODFORM_KIND)
                || (kind == MODULE_MODFORM_KIND)) {
       /* handle `provide's and `module's in later passes */