diff -up gnupg-2.1.22/configure.ac.build gnupg-2.1.22/configure.ac
--- gnupg-2.1.22/configure.ac.build	2017-07-25 15:31:56.000000000 +0200
+++ gnupg-2.1.22/configure.ac	2017-08-09 16:24:48.466263808 +0200
@@ -89,8 +89,8 @@ AC_GNU_SOURCE
 # CFLAGS (they are restored at the end of the configure script).  This
 # is because some configure checks don't work with -Werror, but we'd
 # like to use -Werror with our build.
-CFLAGS_orig=$CFLAGS
-CFLAGS=
+#CFLAGS_orig=$CFLAGS
+#CFLAGS=
 
 # Some status variables.
 have_gpg_error=no
@@ -1682,7 +1682,7 @@ fi
 #
 # Add user CFLAGS.
 #
-CFLAGS="$CFLAGS $CFLAGS_orig"
+# CFLAGS="$CFLAGS $CFLAGS_orig"
 
 #
 # Decide what to build
diff -up gnupg-2.1.22/configure.build gnupg-2.1.22/configure
--- gnupg-2.1.22/configure.build	2017-07-28 19:10:42.000000000 +0200
+++ gnupg-2.1.22/configure	2017-08-09 16:24:48.467263833 +0200
@@ -5100,8 +5100,8 @@ $as_echo "$ac_cv_safe_to_define___extens
 # CFLAGS (they are restored at the end of the configure script).  This
 # is because some configure checks don't work with -Werror, but we'd
 # like to use -Werror with our build.
-CFLAGS_orig=$CFLAGS
-CFLAGS=
+#CFLAGS_orig=$CFLAGS
+#CFLAGS=
 
 # Some status variables.
 have_gpg_error=no
@@ -15676,7 +15676,7 @@ fi
 #
 # Add user CFLAGS.
 #
-CFLAGS="$CFLAGS $CFLAGS_orig"
+# CFLAGS="$CFLAGS $CFLAGS_orig"
 
 #
 # Decide what to build