Fix bug in recent styled_format change

Problem reported by Kaushal Modi in:
http://lists.gnu.org/archive/html/emacs-devel/2017-10/msg00141.html
* src/editfns.c (styled_format): Fix bug where USE_SAFE_ALLOCA was
not always followed by SAFE_FREE.  This bug was introduced in my
patch 2017-09-26T23:31:57Z!eggert@cs.ucla.edu entitled "Avoid some
unnecessary copying in Fformat etc."

1 files changed, 11 insertions, 3 deletions

diff --git a/src/editfns.c b/src/editfns.c
index d88a913c667..e65bd34da87 100644
--- a/src/editfns.c
+++ b/src/editfns.c
@@ -4179,6 +4179,7 @@ styled_format (ptrdiff_t nargs, Lisp_Object *args, bool message)
      multibyte character of the previous string.  This flag tells if we
      must consider such a situation or not.  */
   bool maybe_combine_byte;
+  Lisp_Object val;
   bool arg_intervals = false;
   USE_SAFE_ALLOCA;
   sa_avail -= sizeof initial_buffer;
@@ -4417,7 +4418,10 @@ styled_format (ptrdiff_t nargs, Lisp_Object *args, bool message)
             {
               if (format == end && format - format_start == 2
                   && ! string_intervals (args[0]))
-                return arg;
+                {
+                  val = arg;
+                  goto return_val;
+                }
 
               /* handle case (precision[n] >= 0) */
 
@@ -4862,11 +4866,14 @@ styled_format (ptrdiff_t nargs, Lisp_Object *args, bool message)
     emacs_abort ();
 
   if (! new_result)
-    return args[0];
+    {
+      val = args[0];
+      goto return_val;
+    }
 
   if (maybe_combine_byte)
     nchars = multibyte_chars_in_text ((unsigned char *) buf, p - buf);
-  Lisp_Object val = make_specified_string (buf, nchars, p - buf, multibyte);
+  val = make_specified_string (buf, nchars, p - buf, multibyte);
 
   /* If the format string has text properties, or any of the string
      arguments has text properties, set up text properties of the
@@ -4964,6 +4971,7 @@ styled_format (ptrdiff_t nargs, Lisp_Object *args, bool message)
             }
     }
 
+ return_val:
   /* If we allocated BUF or INFO with malloc, free it too.  */
   SAFE_FREE ();