1 files changed, 3 insertions, 3 deletions

diff --git a/src/minibuf.c b/src/minibuf.c
index f69f06f5ec9..bc86a912dd4 100644
--- a/src/minibuf.c
+++ b/src/minibuf.c
@@ -1726,10 +1726,9 @@ Return nil if there is no valid completion, else t.")
         if (i <= 0) i = 1;
         start_pos= i;
         buffer_nchars -= i;
-        while (1)
+        while (i > 0)
           {
-            tem1 = Fcompare_strings (tem, make_number (start_pos),
-                                     make_number (buffer_nchars + start_pos),
+            tem1 = Fcompare_strings (tem, make_number (start_pos), Qnil,
                                      completion, make_number (0),
                                      make_number (buffer_nchars),
                                      completion_ignore_case ? Qt : Qnil);
@@ -1737,6 +1736,7 @@ Return nil if there is no valid completion, else t.")
             if (EQ (tem1, Qt))
               break;
             i++;
+            buffer_nchars--;
           }
         del_range (1, i + 1);
         SET_PT_BOTH (ZV, ZV_BYTE);