From f4fa74e6f26b7493b8c309a9014246271d6dff4f Mon Sep 17 00:00:00 2001
From: Matthew Flatt <mflatt@racket-lang.org>
Date: Fri, 6 Sep 2019 17:01:34 -0600
Subject: [PATCH] expander: fix reader bug

Fix incorrect comparison of character to EOF. There's a test, already,
but the test fails only if the expander is compiled in safe mode.
---
 pkgs/racket-test-core/tests/racket/read.rktl | 3 ++-
 racket/src/cs/Makefile                       | 2 +-
 racket/src/expander/read/extension.rkt       | 4 ++--
 3 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/pkgs/racket-test-core/tests/racket/read.rktl b/pkgs/racket-test-core/tests/racket/read.rktl
index dda0da359c..49491a5d8b 100644
--- a/pkgs/racket-test-core/tests/racket/read.rktl
+++ b/pkgs/racket-test-core/tests/racket/read.rktl
@@ -1122,7 +1122,8 @@
 		 (parameterize ([print-unreadable #f])
 		   (display x p)))
 	   (err/rt-test (parameterize ([print-unreadable #f])
-			  (write x p))))]
+			  (write x p))
+                        exn:fail?))]
 	[try-good
 	 (lambda (x)
 	   (test (void) (list x)
diff --git a/racket/src/cs/Makefile b/racket/src/cs/Makefile
index da4bffee90..7e99ff9c29 100644
--- a/racket/src/cs/Makefile
+++ b/racket/src/cs/Makefile
@@ -5,7 +5,7 @@ RACKET = ../../bin/racket
 SCHEME = scheme
 
 # Controls whether Racket layers are built as unsafe:
-UNSAFE_COMP = # --unsafe
+UNSAFE_COMP = --unsafe
 
 # Controls whether compiled code is compressed:
 COMPRESS_COMP = # --compress
diff --git a/racket/src/expander/read/extension.rkt b/racket/src/expander/read/extension.rkt
index bbb7bd43e7..58c2162c95 100644
--- a/racket/src/expander/read/extension.rkt
+++ b/racket/src/expander/read/extension.rkt
@@ -43,7 +43,7 @@
                                             in
                                             config))
   (define c (read-char/special in config))
-  (unless (char=? c #\space)
+  (unless (eqv? c #\space)
     (reader-error in config
                   "expected a single space after `~a`"
                   extend-str))
@@ -56,7 +56,7 @@
 (define (read-extension-#! read-recur dispatch-c in config
                            #:get-info? [get-info? #f])
   (define c (read-char/special in config))
-  (unless (char-lang-nonsep? c)
+  (unless (and (char? c) (char-lang-nonsep? c))
     (bad-syntax-error in config (if (char? c)
                                     (string dispatch-c #\! c)
                                     (string dispatch-c #\!))))