Travis: Test build against system libs (& Qt4)

.travis.yml

@@ -25,6 +25,8 @@ env:
     - HOST=arm-linux-gnueabihf PACKAGES="g++-arm-linux-gnueabihf" DEP_OPTS="NO_QT=1" CHECK_DOC=1 GOAL="install" BITCOIN_CONFIG="--enable-glibc-back-compat --enable-reduce-exports"
 # Win32
     - HOST=i686-w64-mingw32 DPKG_ADD_ARCH="i386" DEP_OPTS="NO_QT=1" PACKAGES="python3 nsis g++-mingw-w64-i686 wine1.6" RUN_TESTS=true GOAL="install" BITCOIN_CONFIG="--enable-reduce-exports"
+# Qt4 & system libs
+    - HOST=x86_64-unknown-linux-gnu PACKAGES="python3-zmq qt4-dev-tools libssl-dev libevent-dev bsdmainutils libboost-system-dev libboost-filesystem-dev libboost-chrono-dev libboost-program-options-dev libboost-test-dev libboost-thread-dev libdb5.1++-dev libminiupnpc-dev libzmq3-dev libprotobuf-dev protobuf-compiler libqrencode-dev xvfb" NO_DEPENDS=1 NEED_XVFB=1 RUN_TESTS=true GOAL="install" BITCOIN_CONFIG="--enable-zmq --with-incompatible-bdb --enable-glibc-back-compat --enable-reduce-exports --with-gui=qt4 CPPFLAGS=-DDEBUG_LOCKORDER"
 # 32-bit + dash
     - HOST=i686-pc-linux-gnu PACKAGES="g++-multilib python3-zmq" DEP_OPTS="NO_QT=1" RUN_TESTS=true GOAL="install" BITCOIN_CONFIG="--enable-zmq --enable-glibc-back-compat --enable-reduce-exports LDFLAGS=-static-libstdc++" USE_SHELL="/bin/dash"
 # Win64
@@ -49,7 +51,9 @@ before_script:
     - mkdir -p depends/SDKs depends/sdk-sources
     - if [ -n "$OSX_SDK" -a ! -f depends/sdk-sources/MacOSX${OSX_SDK}.sdk.tar.gz ]; then curl --location --fail $SDK_URL/MacOSX${OSX_SDK}.sdk.tar.gz -o depends/sdk-sources/MacOSX${OSX_SDK}.sdk.tar.gz; fi
     - if [ -n "$OSX_SDK" -a -f depends/sdk-sources/MacOSX${OSX_SDK}.sdk.tar.gz ]; then tar -C depends/SDKs -xf depends/sdk-sources/MacOSX${OSX_SDK}.sdk.tar.gz; fi
-    - make $MAKEJOBS -C depends HOST=$HOST $DEP_OPTS
+    - if [ -z "$NO_DEPENDS" ]; then make $MAKEJOBS -C depends HOST=$HOST $DEP_OPTS; fi
+    # Start xvfb if needed, as documented at https://docs.travis-ci.com/user/gui-and-headless-browsers/#Using-xvfb-to-Run-Tests-That-Require-a-GUI
+    - if [ "$NEED_XVFB" = 1 ]; then export DISPLAY=:99.0; /sbin/start-stop-daemon --start --pidfile /tmp/custom_xvfb_99.pid --make-pidfile --background --exec /usr/bin/Xvfb -- :99 -ac; fi
 script:
     - if [ "$CHECK_DOC" = 1 -a "$TRAVIS_REPO_SLUG" = "bitcoin/bitcoin" -a "$TRAVIS_PULL_REQUEST" = "false" ]; then while read LINE; do travis_retry gpg --keyserver hkp://subset.pool.sks-keyservers.net --recv-keys $LINE; done < contrib/verify-commits/trusted-keys; fi
     - if [ "$CHECK_DOC" = 1 -a "$TRAVIS_REPO_SLUG" = "bitcoin/bitcoin" -a "$TRAVIS_PULL_REQUEST" = "false" ]; then git fetch --unshallow; fi
@@ -58,7 +62,7 @@ script:
     - if [ -n "$USE_SHELL" ]; then export CONFIG_SHELL="$USE_SHELL"; fi
     - OUTDIR=$BASE_OUTDIR/$TRAVIS_PULL_REQUEST/$TRAVIS_JOB_NUMBER-$HOST
     - BITCOIN_CONFIG_ALL="--disable-dependency-tracking --prefix=$TRAVIS_BUILD_DIR/depends/$HOST --bindir=$OUTDIR/bin --libdir=$OUTDIR/lib"
-    - depends/$HOST/native/bin/ccache --max-size=$CCACHE_SIZE
+    - if [ -z "$NO_DEPENDS" ]; then depends/$HOST/native/bin/ccache --max-size=$CCACHE_SIZE; fi
     - test -n "$USE_SHELL" && eval '"$USE_SHELL" -c "./autogen.sh"' || ./autogen.sh
     - mkdir build && cd build
     - ../configure --cache-file=config.cache $BITCOIN_CONFIG_ALL $BITCOIN_CONFIG || ( cat config.log && false)