expander: fix problem with syntax-local-expand-expression

Closes #1984

pkgs/racket-test-core/tests/racket/macro.rktl

@@ -1882,6 +1882,28 @@
   (module* a #f (bind-and-expand x x))
   (module* b #f (bind-and-expand x (list x))))
 
+;; ----------------------------------------
+;; Make sure it's ok to produce an already-expanded
+;; expression in a definition context
+
+(module macro-with-syntax-local-expand-expression-in-a-definition-context racket/base
+  (require (for-syntax racket/base))
+
+  (define-syntax (m stx)
+    (syntax-case stx ()
+      [(_ e)
+       (let ()
+         (define-values (new-stx new-exp)
+           (syntax-local-expand-expression #'e #t))
+         new-exp)]))
+
+  (m 5)
+
+  (let ()
+    (define whatever 10)
+    (m (+ 1 2))
+    'ok))
+
 ;; ----------------------------------------
 
 (report-errs)

racket/src/expander/expand/main.rkt

@@ -209,6 +209,8 @@
                                        " extra bindings or scopes in the current context")
                         (and (not (parsed? exp-s)) exp-s)))
   (cond
+    [(expand-context-only-immediate? ctx)
+     s]
     [(parsed? exp-s) exp-s]
     [else
      (define result-s (syntax-track-origin exp-s s))

racket/src/racket/src/startup.inc

@@ -38965,6 +38965,8 @@ static const char *startup_source =
 "                  \" extra bindings or scopes in the current context\")"
 "(if(not(parsed? exp-s_0)) exp-s_0 #f)))"
 "(void))"
+"(if(expand-context-only-immediate? ctx_18)"
+"(let-values() s_45)"
 "(if(parsed? exp-s_0)"
 "(let-values() exp-s_0)"
 "(let-values()"
@@ -38977,7 +38979,7 @@ static const char *startup_source =
 "(if(if(expand-context-to-parsed? ctx_18)(free-id-set-empty?(expand-context-stops ctx_18)) #f)"
 "(let-values(((result-s115_0) result-s_1)((ctx116_0) ctx_18))"
 "(expand7.1 #f #f #f #f result-s115_0 ctx116_0))"
-" result-s_1)))))))))))"
+" result-s_1))))))))))))"
 "(define-values"
 "(make-explicit)"
 "(lambda(ctx_19 sym_62 s_307 disarmed-s_2)"