Error with OpenWrt make

After downloading the trunk version

CD openwrt/trunk/
SVN up
./scripts/feeds update-a
./scripts/feeds Install-a

The Make Defconfig error occurred

Checking *working-make* ... ok.
Checking *case-sensitive-fs* ... ok.
Checking *getopt* ... ok.
Checking *fileutils* ... ok.
Checking *working-gcc* ... ok.
Checking *working-g++* ... ok.
Checking *ncurses* ... ok.
Checking *zlib* ... ok.
Checking *gawk* ... ok.
Checking *unzip* ... ok.
Checking *bzip2* ... ok.
Checking *perl* ... ok.
Checking */usr/bin/python2.7* ... ok.
Checking *wget* ... ok.
Checking *git* ... ok.
Checking *gnutar* ... ok.
Checking *svn* ... ok.
Checking *libssl* ... failed.
Checking *openssl* ... ok.
Checking *gnu-find* ... ok.
Checking *getopt-extended* ... ok.
Checking *file* ... ok.
Checking *non-root* ... ok.

Build dependency:please Install the OpenSSL library (with development headers)

Prerequisite check failed. Use Force=1 to override.
MAKE[1]: * * * [tmp/.prereq-build] Error 1
Make: * * * [World] Error 2

This error also requires the installation of two packages:

sudo apt-get install Libssl-dev
sudo apt-get install libssl0.9.8

After the successful execution of make defconfig, OK.