1 files changed, 4 insertions, 1 deletions

diff --git a/src/lread.c b/src/lread.c
index 14c6f608b86..7e4f3d2f109 100644
--- a/src/lread.c
+++ b/src/lread.c
@@ -1637,7 +1637,10 @@ read_integer (readcharfun, radix)
           else if (c >= 'A' && c <= 'Z')
             digit = c - 'A' + 10;
           else
-            break;
+            {
+              UNREAD (c);
+              break;
+            }
 
           if (digit < 0 || digit >= radix)
             invalid_p = 1;