From 4f966c0a680becf29d2174c2e9d53c16a18bf936 Mon Sep 17 00:00:00 2001
From: naruse <naruse@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Fri, 6 Oct 2017 11:17:38 +0000
Subject: [PATCH] configure.ac: detect mandoc and set MANTYPE=doc

OpenBSD uses mandoc [Feature #13981] [ruby-core:83146]
Note: AC_PATH_PROGS_FEATURE_CHECK is autoconf 2.62 feature,
but current CRuby declares AC_PREREQ(2.67); it's safe to use.
Patched by kernigh (George Koehler)

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@60129 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 configure.ac | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/configure.ac b/configure.ac
index 8ea969412f..e6cd95cc9d 100644
--- a/configure.ac
+++ b/configure.ac
@@ -4523,8 +4523,18 @@ AC_ARG_WITH(mantype,
 			[AC_MSG_ERROR(invalid man type: $withval)])
 		])
 AS_IF([test -z "$MANTYPE"], [
-	AC_PATH_PROGS(NROFF, nroff awf, /bin/false, "/usr/bin:/usr/ucb")
-	AS_IF([${NROFF} -mdoc ${srcdir}/man/ruby.1 >/dev/null 2>&1], [
+	dnl Looks for nroff with -mdoc support.
+	AC_CACHE_VAL([ac_cv_path_NROFF], [
+		AC_PATH_PROGS_FEATURE_CHECK([NROFF],
+			[nroff awf mandoc],
+			[$ac_path_NROFF -mdoc ${srcdir}/man/ruby.1 \
+				>/dev/null 2>&1 &&
+				ac_cv_path_NROFF=$ac_path_NROFF \
+				ac_path_NROFF_found=:],
+			[], ["/usr/bin:/usr/ucb"]
+		)
+	])
+	AS_IF([test -n "$ac_cv_path_NROFF"], [
 		MANTYPE=doc
 	], [
 		MANTYPE=man