Avoid aborts when input-method-function changes this-command-keys (Bug#19774)

 src/keyboard.c (read_char): Make sure this_single_command_key_start
 is in sync with this_command_key_count, around the call to
 input-method-function.

1 files changed, 4 insertions, 0 deletions

diff --git a/src/keyboard.c b/src/keyboard.c
index 4f6a4414a04..ab57553e7d3 100644
--- a/src/keyboard.c
+++ b/src/keyboard.c
@@ -3034,6 +3034,7 @@ read_char (int commandflag, Lisp_Object map,
       Lisp_Object keys;
       ptrdiff_t key_count;
       bool key_count_reset;
+      ptrdiff_t command_key_start;
       struct gcpro gcpro1;
       ptrdiff_t count = SPECPDL_INDEX ();
 
@@ -3057,6 +3058,7 @@ read_char (int commandflag, Lisp_Object map,
       /* Save the this_command_keys status.  */
       key_count = this_command_key_count;
       key_count_reset = this_command_key_count_reset;
+      command_key_start = this_single_command_key_start;
 
       if (key_count > 0)
         keys = Fcopy_sequence (this_command_keys);
@@ -3067,6 +3069,7 @@ read_char (int commandflag, Lisp_Object map,
       /* Clear out this_command_keys.  */
       this_command_key_count = 0;
       this_command_key_count_reset = 0;
+      this_single_command_key_start = 0;
 
       /* Now wipe the echo area.  */
       if (!NILP (echo_area_buffer[0]))
@@ -3090,6 +3093,7 @@ read_char (int commandflag, Lisp_Object map,
          and this_command_keys state.  */
       this_command_key_count = key_count;
       this_command_key_count_reset = key_count_reset;
+      this_single_command_key_start = command_key_start;
       if (key_count > 0)
         this_command_keys = keys;