Minor improvements to make_formatted_string.

* alloc.c (make_formatted_string): Prefer int to ptrdiff_t
where int is good enough, as vsprintf returns an int.
* lisp.h (make_formatted_string): Add ATTRIBUTE_FORMAT_PRINTF.

3 files changed, 10 insertions, 2 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 4e69496fadd..d5a8abe5c56 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,10 @@
+2012-07-09  Paul Eggert  <eggert@cs.ucla.edu>
+
+        Minor improvements to make_formatted_string.
+        * alloc.c (make_formatted_string): Prefer int to ptrdiff_t
+        where int is good enough, as vsprintf returns an int.
+        * lisp.h (make_formatted_string): Add ATTRIBUTE_FORMAT_PRINTF.
+
 2012-07-09  Dmitry Antipov  <dmantipov@yandex.ru>
 
         Use make_formatted_string to avoid double length calculation.
diff --git a/src/alloc.c b/src/alloc.c
index 739ec40c45c..a5c2e20d0c9 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -2524,7 +2524,7 @@ Lisp_Object
 make_formatted_string (char *buf, const char *format, ...)
 {
   va_list ap;
-  ptrdiff_t length;
+  int length;
 
   va_start (ap, format);
   length = vsprintf (buf, format, ap);
diff --git a/src/lisp.h b/src/lisp.h
index 466287b798a..440a37c8bfb 100644
--- a/src/lisp.h
+++ b/src/lisp.h
@@ -2611,7 +2611,8 @@ extern Lisp_Object list5 (Lisp_Object, Lisp_Object, Lisp_Object, Lisp_Object,
 extern Lisp_Object allocate_misc (void);
 extern _Noreturn void string_overflow (void);
 extern Lisp_Object make_string (const char *, ptrdiff_t);
-extern Lisp_Object make_formatted_string (char *, const char *, ...);
+extern Lisp_Object make_formatted_string (char *, const char *, ...)
+  ATTRIBUTE_FORMAT_PRINTF (2, 3);
 extern Lisp_Object make_unibyte_string (const char *, ptrdiff_t);
 extern Lisp_Object make_multibyte_string (const char *, ptrdiff_t, ptrdiff_t);
 extern Lisp_Object make_event_array (int, Lisp_Object *);