Don't use printf %n

gnulib possible use of %n at runtime deduced from a report by naddy@

textproc/recutils/Makefile

@@ -1,8 +1,9 @@
-# $OpenBSD: Makefile,v 1.2 2021/03/27 17:22:37 ajacoutot Exp $
+# $OpenBSD: Makefile,v 1.3 2021/08/31 17:41:19 jca Exp $
 
 COMMENT =	tools to access human-editable plaintext record files
 
 DISTNAME =	recutils-1.8
+REVISION =	0
 
 SHARED_LIBS +=  rec                       0.0 # 1.0
 

textproc/recutils/patches/patch-lib_vasnprintf_c

@@ -0,0 +1,20 @@
+$OpenBSD: patch-lib_vasnprintf_c,v 1.1 2021/08/31 17:41:19 jca Exp $
+
+Don't use printf %n.
+https://git.savannah.gnu.org/cgit/gnulib.git/commit/lib/vasnprintf.c?id=b954346c6101860c7b462d1b286641d1307afd6c
+
+Index: lib/vasnprintf.c
+--- lib/vasnprintf.c.orig
++++ lib/vasnprintf.c
+@@ -4871,10 +4871,7 @@ VASNPRINTF (DCHAR_T *resultbuf, size_t *lengthp,
+ #endif
+                   *fbp = dp->conversion;
+ #if USE_SNPRINTF
+-# if ! (((__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 3))        \
+-         && !defined __UCLIBC__)                                            \
+-        || (defined __APPLE__ && defined __MACH__)                          \
+-        || (defined _WIN32 && ! defined __CYGWIN__))
++# if 0
+                 fbp[1] = '%';
+                 fbp[2] = 'n';
+                 fbp[3] = '\0';