1 files changed, 43 insertions, 19 deletions

diff --git a/src/callint.c b/src/callint.c
index c02ea33a7bd..5368ba84cf7 100644
--- a/src/callint.c
+++ b/src/callint.c
@@ -47,6 +47,11 @@ static Lisp_Object preserved_fns;
 /* Marker used within call-interactively to refer to point.  */
 static Lisp_Object point_marker;
 
+/* Buffer for the prompt text used in Fcall_interactively.  */
+static char *callint_message;
+
+/* Allocated length of that buffer.  */
+static int callint_message_size;
 
 /* This comment supplies the doc string for interactive,
    for make-docfile to see.  We cannot put this in the real DEFUN
@@ -197,7 +202,6 @@ Otherwise, this is done only if an arg is read using the minibuffer.")
 
   register int i, j;
   int count, foo;
-  char prompt[100];
   char prompt1[100];
   char *tem1;
   int arg_from_tty = 0;
@@ -413,13 +417,26 @@ Otherwise, this is done only if an arg is read using the minibuffer.")
             ? (unsigned char *) ""
               : XSTRING (visargs[j])->data;
 
-      doprnt (prompt, sizeof prompt, prompt1, (char *)0,
-              j - 1, argstrings + 1);
+      /* Process the format-string in prompt1, putting the output
+         into callint_message.  Make callint_message bigger if necessary.
+         We don't use a buffer on the stack, because the contents
+         need to stay stable for a while.  */
+      while (1)
+        {
+          int nchars = doprnt (callint_message, callint_message_size,
+                               prompt1, (char *)0,
+                               j - 1, argstrings + 1);
+          if (nchars < callint_message_size)
+            break;
+          callint_message_size *= 2;
+          callint_message
+            = (char *) xrealloc (callint_message, callint_message_size);
+        }
 
       switch (*tem)
         {
         case 'a':               /* Symbol defined as a function */
-          visargs[i] = Fcompleting_read (build_string (prompt),
+          visargs[i] = Fcompleting_read (build_string (callint_message),
                                          Vobarray, Qfboundp, Qt, Qnil, Qnil);
           /* Passing args[i] directly stimulates compiler bug */
           teml = visargs[i];
@@ -430,17 +447,17 @@ Otherwise, this is done only if an arg is read using the minibuffer.")
           args[i] = Fcurrent_buffer ();
           if (EQ (selected_window, minibuf_window))
             args[i] = Fother_buffer (args[i], Qnil);
-          args[i] = Fread_buffer (build_string (prompt), args[i], Qt);
+          args[i] = Fread_buffer (build_string (callint_message), args[i], Qt);
           break;
 
         case 'B':               /* Name of buffer, possibly nonexistent */
-          args[i] = Fread_buffer (build_string (prompt),
+          args[i] = Fread_buffer (build_string (callint_message),
                                   Fother_buffer (Fcurrent_buffer (), Qnil),
                                   Qnil);
           break;
 
         case 'c':               /* Character */
-          message1 (prompt);
+          message1 (callint_message);
           args[i] = Fread_char ();
           /* Passing args[i] directly stimulates compiler bug */
           teml = args[i];
@@ -448,7 +465,7 @@ Otherwise, this is done only if an arg is read using the minibuffer.")
           break;
 
         case 'C':               /* Command: symbol with interactive function */
-          visargs[i] = Fcompleting_read (build_string (prompt),
+          visargs[i] = Fcompleting_read (build_string (callint_message),
                                          Vobarray, Qcommandp, Qt, Qnil, Qnil);
           /* Passing args[i] directly stimulates compiler bug */
           teml = visargs[i];
@@ -463,28 +480,30 @@ Otherwise, this is done only if an arg is read using the minibuffer.")
           break;
 
         case 'D':               /* Directory name. */
-          args[i] = Fread_file_name (build_string (prompt), Qnil,
+          args[i] = Fread_file_name (build_string (callint_message), Qnil,
                                      current_buffer->directory, Qlambda, Qnil);
           break;
 
         case 'f':               /* Existing file name. */
-          args[i] = Fread_file_name (build_string (prompt),
+          args[i] = Fread_file_name (build_string (callint_message),
                                      Qnil, Qnil, Qlambda, Qnil);
           break;
 
         case 'F':               /* Possibly nonexistent file name. */
-          args[i] = Fread_file_name (build_string (prompt),
+          args[i] = Fread_file_name (build_string (callint_message),
                                      Qnil, Qnil, Qnil, Qnil);
           break;
 
         case 'k':               /* Key sequence. */
-          args[i] = Fread_key_sequence (build_string (prompt), Qnil, Qnil, Qnil);
+          args[i] = Fread_key_sequence (build_string (callint_message),
+                                        Qnil, Qnil, Qnil);
           teml = args[i];
           visargs[i] = Fkey_description (teml);
           break;
 
         case 'K':               /* Key sequence to be defined. */
-          args[i] = Fread_key_sequence (build_string (prompt), Qnil, Qt, Qnil);
+          args[i] = Fread_key_sequence (build_string (callint_message),
+                                        Qnil, Qt, Qnil);
           teml = args[i];
           visargs[i] = Fkey_description (teml);
           break;
@@ -518,7 +537,7 @@ Otherwise, this is done only if an arg is read using the minibuffer.")
             goto have_prefix_arg;
         case 'n':               /* Read number from minibuffer.  */
           do
-            args[i] = Fread_minibuffer (build_string (prompt), Qnil);
+            args[i] = Fread_minibuffer (build_string (callint_message), Qnil);
           while (! NUMBERP (args[i]));
           visargs[i] = last_minibuf_string;
           break;
@@ -549,11 +568,12 @@ Otherwise, this is done only if an arg is read using the minibuffer.")
           break;
 
         case 's':               /* String read via minibuffer.  */
-          args[i] = Fread_string (build_string (prompt), Qnil, Qnil);
+          args[i] = Fread_string (build_string (callint_message), Qnil, Qnil);
           break;
 
         case 'S':               /* Any symbol.  */
-          visargs[i] = Fread_string (build_string (prompt), Qnil, Qnil);
+          visargs[i] = Fread_string (build_string (callint_message),
+                                     Qnil, Qnil);
           /* Passing args[i] directly stimulates compiler bug */
           teml = visargs[i];
           args[i] = Fintern (teml, Qnil);
@@ -561,17 +581,17 @@ Otherwise, this is done only if an arg is read using the minibuffer.")
 
         case 'v':               /* Variable name: symbol that is
                                    user-variable-p. */
-          args[i] = Fread_variable (build_string (prompt));
+          args[i] = Fread_variable (build_string (callint_message));
           visargs[i] = last_minibuf_string;
           break;
 
         case 'x':               /* Lisp expression read but not evaluated */
-          args[i] = Fread_minibuffer (build_string (prompt), Qnil);
+          args[i] = Fread_minibuffer (build_string (callint_message), Qnil);
           visargs[i] = last_minibuf_string;
           break;
 
         case 'X':               /* Lisp expression read and evaluated */
-          args[i] = Feval_minibuffer (build_string (prompt), Qnil);
+          args[i] = Feval_minibuffer (build_string (callint_message), Qnil);
           visargs[i] = last_minibuf_string;
           break;
 
@@ -687,6 +707,10 @@ syms_of_callint ()
   Qmouse_leave_buffer_hook = intern ("mouse-leave-buffer-hook");
   staticpro (&Qmouse_leave_buffer_hook);
 
+  callint_message_size = 100;
+  callint_message = (char *) xmalloc (callint_message_size);
+
+
   DEFVAR_KBOARD ("prefix-arg", Vprefix_arg,
     "The value of the prefix argument for the next editing command.\n\
 It may be a number, or the symbol `-' for just a minus sign as arg,\n\