diff --git a/misc/check-doc.sh b/misc/check-doc.sh
new file mode 100644
index 0000000..73b169a
--- /dev/null
+++ b/misc/check-doc.sh
@@ -0,0 +1,43 @@
+#!/bin/sh
+prog=$0
+
+die() {
+	echo "$@"
+	exit 1
+}
+
+want() {
+	test -e "$1" && return
+	echo "$prog: missing $1"
+	echo "$prog: run this script from the top of a gmqcc source tree"
+	exit 1
+}
+
+for i in opts.def          \
+         doc/gmqcc.1       \
+         gmqcc.ini.example
+do want "$i"; done
+
+# y/_ABCDEFGHIJKLMNOPQRSTUVWXYZ/-abcdefghijklmnopqrstuvwxyz/;
+check_opt() {
+	opt_def_name=$1
+	arg_char=$2
+
+	for i in $(sed -ne \
+	'/^#ifdef GMQCC_TYPE_'${opt_def_name}'$/,/^#endif/{
+		/GMQCC_DEFINE_FLAG/{
+			s/^.*GMQCC_DEFINE_FLAG(\([^,)]*\)[),].*$/\1/;p;
+		}
+	}' opts.def)
+	do
+		opt=$(echo "$i" | tr -- '_A-Z' '-a-z')
+		grep -qF -- ".It Fl "${arg_char}" Ns Cm $opt" \
+			doc/gmqcc.1 || echo "doc/gmqcc.1: missing: -${arg_char}$opt"
+		grep -q -- "[^a-zA-Z_]$i[^a-zA-Z_]" \
+			gmqcc.ini.example || echo "gmqcc.ini.example: missing: $i"
+	done
+}
+
+check_opt FLAGS f
+check_opt WARNS W
+check_opt OPTIMIZATIONS O