diff --git a/configure b/configure
index 65e73887b..641657b12 100755
--- a/configure
+++ b/configure
@@ -4498,9 +4498,9 @@ $as_echo "no" >&6; }
 
 fi
 
-fi
 default_cflags=yes
 fi
+fi
 ac_ext=c
 ac_cpp='$CPP $CPPFLAGS'
 ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
diff --git a/configure.ac b/configure.ac
index 61984f6f1..4517b1c20 100644
--- a/configure.ac
+++ b/configure.ac
@@ -255,9 +255,9 @@ if $CC --version 2>&1 | grep "clang" >/dev/null; then
 	:
 else
 ACX_CHECK_COMPILER_FLAG(O2, [CFLAGS="$CFLAGS -O2"])
-fi
 default_cflags=yes
 fi
+fi
 AC_PROG_CC
 ACX_DEPFLAG
 ACX_DETERMINE_EXT_FLAGS_UNBOUND
diff --git a/doc/Changelog b/doc/Changelog
index d73b74d8d..0e0a82c4a 100644
--- a/doc/Changelog
+++ b/doc/Changelog
@@ -2,6 +2,8 @@
 	- Fix timestamp failure because of clang optimizer failure, by
 	  disabling -O2 when the compiler --version is clang.
 	- iana port update.
+	- Also disable -flto for clang, to make incep-expi signature check
+	  work.
 
 12 December 2017: Ralph
 	- Fix qname-minimisation documentation (A QTYPE, not NS)