1 files changed, 5 insertions, 2 deletions

diff --git a/src/fns.c b/src/fns.c
index ded6f344aad..c89bd8144e7 100644
--- a/src/fns.c
+++ b/src/fns.c
@@ -1766,6 +1766,9 @@ changing the value of a sequence `foo'.  */)
     }
   else if (STRINGP (seq))
     {
+      if (!CHARACTERP (elt))
+        return seq;
+
       ptrdiff_t i, ibyte, nchars, nbytes, cbytes;
       int c;
 
@@ -1784,7 +1787,7 @@ changing the value of a sequence `foo'.  */)
               cbytes = 1;
             }
 
-          if (!FIXNUMP (elt) || c != XFIXNUM (elt))
+          if (c != XFIXNUM (elt))
             {
               ++nchars;
               nbytes += cbytes;
@@ -1814,7 +1817,7 @@ changing the value of a sequence `foo'.  */)
                   cbytes = 1;
                 }
 
-              if (!FIXNUMP (elt) || c != XFIXNUM (elt))
+              if (c != XFIXNUM (elt))
                 {
                   unsigned char *from = SDATA (seq) + ibyte;
                   unsigned char *to   = SDATA (tem) + nbytes;