build: don't rely on support for '%j' printf format

* src/factor.c (print_uintmaxes): Replace with PRIuMAX.
* src/join.c (check_order): Likewise.
* cfg.mk (sc_check-j-printf-format): Add a syntax-check rule
to flag new cases of this.

3 files changed, 12 insertions, 2 deletions

diff --git a/cfg.mk b/cfg.mk
index 362b0603a..46652b017 100644
--- a/cfg.mk
+++ b/cfg.mk
@@ -191,6 +191,16 @@ sc_check-I18N-AUTHORS:
 		    '$$(LIBICONV)' 1>&2; exit 1; };			\
 	  done
 
+# Ensure %j is not used for intmax_t as it's not universally supported.
+# There are issues on HPUX for example.  But note that %ju was used between
+# coreutils 8.13 (2011-10) and 8.20 (2012-10) without any reported issue,
+# and the particular issue this check is associated with was for %*jx.
+# So we may be able to relax this restriction soon.
+sc_prohibit-j-printf-format:
+	@cd $(srcdir)/src && GIT_PAGER= git grep -n '%[0*]*j[udx]' *.c	\
+	  && { echo '$(ME): Use PRI*MAX instead of %j' 1>&2; exit 1; }  \
+	  || :
+
 # Look for lines longer than 80 characters, except omit:
 # - program-generated long lines in diff headers,
 # - tests involving long checksum lines, and
diff --git a/src/factor.c b/src/factor.c
index 4c2af9811..be5a36cd5 100644
--- a/src/factor.c
+++ b/src/factor.c
@@ -2313,7 +2313,7 @@ print_uintmaxes (uintmax_t t1, uintmax_t t0)
   uintmax_t q, r;
 
   if (t1 == 0)
-    printf ("%ju", t0);
+    printf ("%"PRIuMAX, t0);
   else
     {
       /* Use very plain code here since it seems hard to write fast code
diff --git a/src/join.c b/src/join.c
index e39ed8725..eb87301c7 100644
--- a/src/join.c
+++ b/src/join.c
@@ -400,7 +400,7 @@ check_order (const struct line *prev,
 
               error ((check_input_order == CHECK_ORDER_ENABLED
                       ? EXIT_FAILURE : 0),
-                     0, _("%s:%ju: is not sorted: %.*s"),
+                     0, _("%s:%"PRIuMAX": is not sorted: %.*s"),
                      g_names[whatfile - 1], line_no[whatfile - 1],
                      (int) len, current->buf.buffer);