diff --git a/racket/src/native-libs/build.rkt b/racket/src/native-libs/build.rkt
index 1a79400920..082437c984 100644
--- a/racket/src/native-libs/build.rkt
+++ b/racket/src/native-libs/build.rkt
@@ -138,6 +138,9 @@
 ;; (i.e., auto-find a suitable font) as implemented by `racket/draw`
 (define-runtime-path pango-emoji-patch "patches/pango-emoji.patch")
 
+;; Merge a Pango patch that fixes a decoding problem
+(define-runtime-path pango-emojiiter-patch "patches/pango-emojiiter.patch")
+
 ;; Needed when building with old GCC, such as 4.0:
 (define-runtime-path gmp-weak-patch "patches/gmp-weak.patch")
 
@@ -529,7 +532,8 @@
                                   (list coretext-patch
                                         coretext-fontreg-patch
                                         coretext-nullarray
-                                        win32text-patch)
+                                        win32text-patch
+                                        pango-emojiiter-patch)
                                   (if (and mac? m32?)
                                       (list pango-surrogate-patch)
                                       null)
diff --git a/racket/src/native-libs/patches/pango-emojiiter.patch b/racket/src/native-libs/patches/pango-emojiiter.patch
new file mode 100644
index 0000000000..8c920676e8
--- /dev/null
+++ b/racket/src/native-libs/patches/pango-emojiiter.patch
@@ -0,0 +1,31 @@
+commit 71aaeaf020340412b8d012fe23a556c0420eda5f
+Author: Matthias Clasen <mclasen@redhat.com>
+Date:   Fri Aug 17 22:29:36 2018 -0400
+
+    Prevent an assertion with invalid Unicode sequences
+    
+    Invalid Unicode sequences, such as 0x2665 0xfe0e 0xfe0f,
+    can trick the Emoji iter code into returning an empty
+    segment, which then triggers an assertion in the itemizer.
+    
+    Prevent this by ensuring that we make progress.
+    
+    This issue was reported by Jeffrey M.
+
+diff --git a/pango/pango-emoji.c b/pango/pango-emoji.c
+index 0e332dff..29472452 100644
+--- old/a/pango/pango-emoji.c
++++ new/b/pango/pango-emoji.c
+@@ -253,6 +253,12 @@ _pango_emoji_iter_next (PangoEmojiIter *iter)
+     if (iter->is_emoji == PANGO_EMOJI_TYPE_IS_EMOJI (current_emoji_type))
+     {
+       iter->is_emoji = !PANGO_EMOJI_TYPE_IS_EMOJI (current_emoji_type);
++
++      /* Make sure we make progress.  Weird sequences, like a VC15 followed
++       * by VC16, can trick us into stalling otherwise. */
++      if (iter->start == iter->end)
++        iter->end = g_utf8_next_char (iter->end);
++
+       return TRUE;
+     }
+   }