Warn when pkg.m4 is missing at autoreconf time.

diff --git a/configure.ac b/configure.ac
index 4f146f572b140d7ae735ccac7a82ebf2cac3ae87..ee6f820faac510c31563bf97ddb89f068af6c027 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -42,6 +42,9 @@ AC_DEFINE([_GNU_SOURCE], [1],
   [Define _GNU_SOURCE so that we get all necessary prototypes]
 )
 
+# Warn when pkg.m4 is missing
+m4_pattern_forbid([^_?PKG_[A-Z_]+$],[*** pkg.m4 missing, please install pkg-config])
+
 PDNS_WITH_LUAJIT
 AS_IF([test "x$with_luajit" = "xno"], [
   PDNS_WITH_LUA