Merge #13458: gui: Drop qt4 support

af6ac3b677 doc: Remove mention of Qt4 from build docs (Wladimir J. van der Laan) 462c71f71b test: Update travis to not test Qt4 anymore (Wladimir J. van der Laan) 907f73bbc5 gui: Remove QT_VERSION fallbacks for Qt < 5 (Wladimir J. van der Laan) bad068ad9f build: Build system changes to support only Qt5 (Wladimir J. van der Laan) Pull request description: Implements #8263. Qt4.x has been EOL since 2015, and at least Gentoo has, or is going to drop support for it. I wouldn't be surprised if other Linux distributions follow. This removes Qt4 detection from the build system, as well as removes all Qt4 fallbacks from the code. Turns out there's more than I expected: this is going to make maintenance of the GUI code, as well as adding new features significantly easier. (I know there's still some references left to qt4 in RPM and Debian build script, but I don't have the knowledge how to fix them) Tree-SHA512: d495924fd4dda6f6566ba44ee96be7cbe62e69ba1ca993b80a8449f78da852b7f1bd3e8200d57cfa1d72233c340eeff4596fb0032ecbddc715d99aea63817d3f
2018-06-24 15:56:00 +02:00 · 2018-06-24 15:56:00 +02:00 · dc53f7f251
parent 5eca4e86d4 af6ac3b677
commit dc53f7f251
30 changed files with 110 additions and 344 deletions
--- a/.travis.yml
+++ b/.travis.yml
@ -35,8 +35,8 @@ env:
    - 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++" CONFIG_SHELL="/bin/dash"
 # x86_64 Linux (uses qt5 dev package instead of depends Qt to speed up build and avoid timeout)
    - HOST=x86_64-unknown-linux-gnu PACKAGES="python3-zmq qtbase5-dev qttools5-dev-tools protobuf-compiler libdbus-1-dev libharfbuzz-dev libprotobuf-dev" DEP_OPTS="NO_QT=1 NO_UPNP=1 DEBUG=1 ALLOW_HOST_PACKAGES=1" RUN_TESTS=true GOAL="install" BITCOIN_CONFIG="--enable-zmq --with-gui=qt5 --enable-glibc-back-compat --enable-reduce-exports CPPFLAGS=-DDEBUG_LOCKORDER"
-# Qt4 & system libs
-    - HOST=x86_64-unknown-linux-gnu PACKAGES="python3-zmq qt4-dev-tools libssl1.0-dev libevent-dev bsdmainutils libboost-system-dev libboost-filesystem-dev libboost-chrono-dev libboost-program-options-dev libboost-test-dev libboost-thread-dev libdb5.3++-dev libminiupnpc-dev libzmq3-dev libprotobuf-dev protobuf-compiler libqrencode-dev xvfb libqt4-dev" 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" DISPLAY=:99.0
+# x86_64 Linux (Qt5 & system libs)
+    - HOST=x86_64-unknown-linux-gnu PACKAGES="python3-zmq qtbase5-dev qttools5-dev-tools libssl1.0-dev libevent-dev bsdmainutils libboost-system-dev libboost-filesystem-dev libboost-chrono-dev libboost-program-options-dev libboost-test-dev libboost-thread-dev libdb5.3++-dev libminiupnpc-dev libzmq3-dev libprotobuf-dev protobuf-compiler libqrencode-dev" NO_DEPENDS=1 RUN_TESTS=true GOAL="install" BITCOIN_CONFIG="--enable-zmq --with-incompatible-bdb --enable-glibc-back-compat --enable-reduce-exports --with-gui=qt5 CPPFLAGS=-DDEBUG_LOCKORDER"
 # x86_64 Linux, No wallet
    - HOST=x86_64-unknown-linux-gnu PACKAGES="python3" DEP_OPTS="NO_WALLET=1" RUN_TESTS=true GOAL="install" BITCOIN_CONFIG="--enable-glibc-back-compat --enable-reduce-exports"
 # Cross-Mac
@ -45,7 +45,7 @@ env:
 before_install:
    - export PATH=$(echo $PATH | tr ':' "\n" | sed '/\/opt\/python/d' | tr "\n" ":" | sed "s|::|:|g")
 install:
-    - env | grep -E '^(CCACHE_|WINEDEBUG|DISPLAY|BOOST_TEST_RANDOM|CONFIG_SHELL)' | tee /tmp/env
+    - env | grep -E '^(CCACHE_|WINEDEBUG|BOOST_TEST_RANDOM|CONFIG_SHELL)' | tee /tmp/env
    - if [[ $HOST = *-mingw32 ]]; then DOCKER_ADMIN="--cap-add SYS_ADMIN"; fi
    - DOCKER_ID=$(docker run $DOCKER_ADMIN -idt --mount type=bind,src=$TRAVIS_BUILD_DIR,dst=$TRAVIS_BUILD_DIR --mount type=bind,src=$CCACHE_DIR,dst=$CCACHE_DIR -w $TRAVIS_BUILD_DIR --env-file /tmp/env ubuntu:18.04)
    - DOCKER_EXEC () { docker exec $DOCKER_ID bash -c "cd $PWD && $*"; }
@ -58,8 +58,6 @@ before_script:
    - if [ -n "$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
    - if [[ $HOST = *-mingw32 ]]; then DOCKER_EXEC update-alternatives --set $HOST-g++ \$\(which $HOST-g++-posix\); fi
    - if [ -z "$NO_DEPENDS" ]; then DOCKER_EXEC CONFIG_SHELL= 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 DOCKER_EXEC /sbin/start-stop-daemon --start --pidfile /tmp/custom_xvfb_99.pid --make-pidfile --background --exec /usr/bin/Xvfb -- :99 -ac; fi
 script:
    - export TRAVIS_COMMIT_LOG=`git log --format=fuller -1`
    - OUTDIR=$BASE_OUTDIR/$TRAVIS_PULL_REQUEST/$TRAVIS_JOB_NUMBER-$HOST
--- a/build-aux/m4/bitcoin_qt.m4
+++ b/build-aux/m4/bitcoin_qt.m4
@ -53,8 +53,8 @@ dnl CAUTION: Do not use this inside of a conditional.
 AC_DEFUN([BITCOIN_QT_INIT],[
  dnl enable qt support
  AC_ARG_WITH([gui],
-    [AS_HELP_STRING([--with-gui@<:@=no|qt4|qt5|auto@:>@],
-    [build bitcoin-qt GUI (default=auto, qt5 tried first)])],
+    [AS_HELP_STRING([--with-gui@<:@=no|qt5|auto@:>@],
+    [build bitcoin-qt GUI (default=auto)])],
    [
     bitcoin_qt_want_version=$withval
     if test "x$bitcoin_qt_want_version" = xyes; then
@ -94,18 +94,17 @@ AC_DEFUN([BITCOIN_QT_CONFIGURE],[
  fi

  if test "x$use_pkgconfig" = xyes; then
-    BITCOIN_QT_CHECK([_BITCOIN_QT_FIND_LIBS_WITH_PKGCONFIG([$2])])
+    BITCOIN_QT_CHECK([_BITCOIN_QT_FIND_LIBS_WITH_PKGCONFIG])
  else
    BITCOIN_QT_CHECK([_BITCOIN_QT_FIND_LIBS_WITHOUT_PKGCONFIG])
  fi

  dnl This is ugly and complicated. Yuck. Works as follows:
-  dnl We can't discern whether Qt4 builds are static or not. For Qt5, we can
-  dnl check a header to find out. When Qt is built statically, some plugins must
-  dnl be linked into the final binary as well. These plugins have changed between
-  dnl Qt4 and Qt5. With Qt5, languages moved into core and the WindowsIntegration
-  dnl plugin was added. Since we can't tell if Qt4 is static or not, it is
-  dnl assumed for windows builds.
+  dnl For Qt5, we can check a header to find out whether Qt is build
+  dnl statically. When Qt is built statically, some plugins must be linked into
+  dnl the final binary as well.
+  dnl With Qt5, languages moved into core and the WindowsIntegration plugin was
+  dnl added.
  dnl _BITCOIN_QT_CHECK_STATIC_PLUGINS does a quick link-check and appends the
  dnl results to QT_LIBS.
  BITCOIN_QT_CHECK([
@ -113,53 +112,40 @@ AC_DEFUN([BITCOIN_QT_CONFIGURE],[
  TEMP_CXXFLAGS=$CXXFLAGS
  CPPFLAGS="$QT_INCLUDES $CPPFLAGS"
  CXXFLAGS="$PIC_FLAGS $CXXFLAGS"
-  if test "x$bitcoin_qt_got_major_vers" = x5; then
-    _BITCOIN_QT_IS_STATIC
-    if test "x$bitcoin_cv_static_qt" = xyes; then
-      _BITCOIN_QT_FIND_STATIC_PLUGINS
-      AC_DEFINE(QT_STATICPLUGIN, 1, [Define this symbol if qt plugins are static])
-      AC_CACHE_CHECK(for Qt < 5.4, bitcoin_cv_need_acc_widget,[
-        AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
-            #include <QtCore/qconfig.h>
-            #ifndef QT_VERSION
-            #  include <QtCore/qglobal.h>
-            #endif
-          ]],
-          [[
-            #if QT_VERSION >= 0x050400
-            choke
-            #endif
-          ]])],
-        [bitcoin_cv_need_acc_widget=yes],
-        [bitcoin_cv_need_acc_widget=no])
-      ])
-      if test "x$bitcoin_cv_need_acc_widget" = xyes; then
-        _BITCOIN_QT_CHECK_STATIC_PLUGINS([Q_IMPORT_PLUGIN(AccessibleFactory)], [-lqtaccessiblewidgets])
-      fi
-      _BITCOIN_QT_CHECK_STATIC_PLUGINS([Q_IMPORT_PLUGIN(QMinimalIntegrationPlugin)],[-lqminimal])
-      AC_DEFINE(QT_QPA_PLATFORM_MINIMAL, 1, [Define this symbol if the minimal qt platform exists])
-      if test "x$TARGET_OS" = xwindows; then
-        _BITCOIN_QT_CHECK_STATIC_PLUGINS([Q_IMPORT_PLUGIN(QWindowsIntegrationPlugin)],[-lqwindows])
-        AC_DEFINE(QT_QPA_PLATFORM_WINDOWS, 1, [Define this symbol if the qt platform is windows])
-      elif test "x$TARGET_OS" = xlinux; then
-        _BITCOIN_QT_CHECK_STATIC_PLUGINS([Q_IMPORT_PLUGIN(QXcbIntegrationPlugin)],[-lqxcb -lxcb-static])
-        AC_DEFINE(QT_QPA_PLATFORM_XCB, 1, [Define this symbol if the qt platform is xcb])
-      elif test "x$TARGET_OS" = xdarwin; then
-        AX_CHECK_LINK_FLAG([[-framework IOKit]],[QT_LIBS="$QT_LIBS -framework IOKit"],[AC_MSG_ERROR(could not iokit framework)])
-        _BITCOIN_QT_CHECK_STATIC_PLUGINS([Q_IMPORT_PLUGIN(QCocoaIntegrationPlugin)],[-lqcocoa])
-        AC_DEFINE(QT_QPA_PLATFORM_COCOA, 1, [Define this symbol if the qt platform is cocoa])
-      fi
+  _BITCOIN_QT_IS_STATIC
+  if test "x$bitcoin_cv_static_qt" = xyes; then
+    _BITCOIN_QT_FIND_STATIC_PLUGINS
+    AC_DEFINE(QT_STATICPLUGIN, 1, [Define this symbol if qt plugins are static])
+    AC_CACHE_CHECK(for Qt < 5.4, bitcoin_cv_need_acc_widget,[
+      AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
+          #include <QtCore/qconfig.h>
+          #ifndef QT_VERSION
+          #  include <QtCore/qglobal.h>
+          #endif
+        ]],
+        [[
+          #if QT_VERSION >= 0x050400
+          choke
+          #endif
+        ]])],
+      [bitcoin_cv_need_acc_widget=yes],
+      [bitcoin_cv_need_acc_widget=no])
+    ])
+    if test "x$bitcoin_cv_need_acc_widget" = xyes; then
+      _BITCOIN_QT_CHECK_STATIC_PLUGINS([Q_IMPORT_PLUGIN(AccessibleFactory)], [-lqtaccessiblewidgets])
    fi
-  else
+    _BITCOIN_QT_CHECK_STATIC_PLUGINS([Q_IMPORT_PLUGIN(QMinimalIntegrationPlugin)],[-lqminimal])
+    AC_DEFINE(QT_QPA_PLATFORM_MINIMAL, 1, [Define this symbol if the minimal qt platform exists])
    if test "x$TARGET_OS" = xwindows; then
-      AC_DEFINE(QT_STATICPLUGIN, 1, [Define this symbol if qt plugins are static])
-      _BITCOIN_QT_CHECK_STATIC_PLUGINS([
-         Q_IMPORT_PLUGIN(qcncodecs)
-         Q_IMPORT_PLUGIN(qjpcodecs)
-         Q_IMPORT_PLUGIN(qtwcodecs)
-         Q_IMPORT_PLUGIN(qkrcodecs)
-         Q_IMPORT_PLUGIN(AccessibleFactory)],
-         [-lqcncodecs -lqjpcodecs -lqtwcodecs -lqkrcodecs -lqtaccessiblewidgets])
+      _BITCOIN_QT_CHECK_STATIC_PLUGINS([Q_IMPORT_PLUGIN(QWindowsIntegrationPlugin)],[-lqwindows])
+      AC_DEFINE(QT_QPA_PLATFORM_WINDOWS, 1, [Define this symbol if the qt platform is windows])
+    elif test "x$TARGET_OS" = xlinux; then
+      _BITCOIN_QT_CHECK_STATIC_PLUGINS([Q_IMPORT_PLUGIN(QXcbIntegrationPlugin)],[-lqxcb -lxcb-static])
+      AC_DEFINE(QT_QPA_PLATFORM_XCB, 1, [Define this symbol if the qt platform is xcb])
+    elif test "x$TARGET_OS" = xdarwin; then
+      AX_CHECK_LINK_FLAG([[-framework IOKit]],[QT_LIBS="$QT_LIBS -framework IOKit"],[AC_MSG_ERROR(could not iokit framework)])
+      _BITCOIN_QT_CHECK_STATIC_PLUGINS([Q_IMPORT_PLUGIN(QCocoaIntegrationPlugin)],[-lqcocoa])
+      AC_DEFINE(QT_QPA_PLATFORM_COCOA, 1, [Define this symbol if the qt platform is cocoa])
    fi
  fi
  CPPFLAGS=$TEMP_CPPFLAGS
@ -167,9 +153,7 @@ AC_DEFUN([BITCOIN_QT_CONFIGURE],[
  ])

  if test "x$use_pkgconfig$qt_bin_path" = xyes; then
-    if test "x$bitcoin_qt_got_major_vers" = x5; then
-      qt_bin_path="`$PKG_CONFIG --variable=host_bins Qt5Core 2>/dev/null`"
-    fi
+    qt_bin_path="`$PKG_CONFIG --variable=host_bins Qt5Core 2>/dev/null`"
  fi

  if test "x$use_hardening" != xno; then
@ -219,11 +203,11 @@ AC_DEFUN([BITCOIN_QT_CONFIGURE],[
    ])
  fi

-  BITCOIN_QT_PATH_PROGS([MOC], [moc-qt${bitcoin_qt_got_major_vers} moc${bitcoin_qt_got_major_vers} moc], $qt_bin_path)
-  BITCOIN_QT_PATH_PROGS([UIC], [uic-qt${bitcoin_qt_got_major_vers} uic${bitcoin_qt_got_major_vers} uic], $qt_bin_path)
-  BITCOIN_QT_PATH_PROGS([RCC], [rcc-qt${bitcoin_qt_got_major_vers} rcc${bitcoin_qt_got_major_vers} rcc], $qt_bin_path)
-  BITCOIN_QT_PATH_PROGS([LRELEASE], [lrelease-qt${bitcoin_qt_got_major_vers} lrelease${bitcoin_qt_got_major_vers} lrelease], $qt_bin_path)
-  BITCOIN_QT_PATH_PROGS([LUPDATE], [lupdate-qt${bitcoin_qt_got_major_vers} lupdate${bitcoin_qt_got_major_vers} lupdate],$qt_bin_path, yes)
+  BITCOIN_QT_PATH_PROGS([MOC], [moc-qt5 moc5 moc], $qt_bin_path)
+  BITCOIN_QT_PATH_PROGS([UIC], [uic-qt5 uic5 uic], $qt_bin_path)
+  BITCOIN_QT_PATH_PROGS([RCC], [rcc-qt5 rcc5 rcc], $qt_bin_path)
+  BITCOIN_QT_PATH_PROGS([LRELEASE], [lrelease-qt5 lrelease5 lrelease], $qt_bin_path)
+  BITCOIN_QT_PATH_PROGS([LUPDATE], [lupdate-qt5 lupdate5 lupdate],$qt_bin_path, yes)

  MOC_DEFS='-DHAVE_CONFIG_H -I$(srcdir)'
  case $host in
@ -262,7 +246,7 @@ AC_DEFUN([BITCOIN_QT_CONFIGURE],[
  ],[
    bitcoin_enable_qt=no
  ])
-  AC_MSG_RESULT([$bitcoin_enable_qt (Qt${bitcoin_qt_got_major_vers})])
+  AC_MSG_RESULT([$bitcoin_enable_qt (Qt5)])

  AC_SUBST(QT_PIE_FLAGS)
  AC_SUBST(QT_INCLUDES)
@ -272,7 +256,7 @@ AC_DEFUN([BITCOIN_QT_CONFIGURE],[
  AC_SUBST(QT_DBUS_LIBS)
  AC_SUBST(QT_TEST_INCLUDES)
  AC_SUBST(QT_TEST_LIBS)
-  AC_SUBST(QT_SELECT, qt${bitcoin_qt_got_major_vers})
+  AC_SUBST(QT_SELECT, qt5)
  AC_SUBST(MOC_DEFS)
 ])

@ -301,7 +285,7 @@ AC_DEFUN([_BITCOIN_QT_CHECK_QT5],[
 ])])

 dnl Internal. Check if the linked version of Qt was built as static libs.
-dnl Requires: Qt5. This check cannot determine if Qt4 is static.
+dnl Requires: Qt5.
 dnl Requires: INCLUDES and LIBS must be populated as necessary.
 dnl Output: bitcoin_cv_static_qt=yes|no
 dnl Output: Defines QT_STATICPLUGIN if plugins are static.
@ -346,58 +330,50 @@ AC_DEFUN([_BITCOIN_QT_CHECK_STATIC_PLUGINS],[
 ])

 dnl Internal. Find paths necessary for linking qt static plugins
-dnl Inputs: bitcoin_qt_got_major_vers. 4 or 5.
 dnl Inputs: qt_plugin_path. optional.
 dnl Outputs: QT_LIBS is appended
 AC_DEFUN([_BITCOIN_QT_FIND_STATIC_PLUGINS],[
-  if test "x$bitcoin_qt_got_major_vers" = x5; then
-      if test "x$qt_plugin_path" != x; then
-        QT_LIBS="$QT_LIBS -L$qt_plugin_path/platforms"
-        if test -d "$qt_plugin_path/accessible"; then
-          QT_LIBS="$QT_LIBS -L$qt_plugin_path/accessible"
-        fi
+    if test "x$qt_plugin_path" != x; then
+      QT_LIBS="$QT_LIBS -L$qt_plugin_path/platforms"
+      if test -d "$qt_plugin_path/accessible"; then
+        QT_LIBS="$QT_LIBS -L$qt_plugin_path/accessible"
      fi
-     if test "x$use_pkgconfig" = xyes; then
-     : dnl
-     m4_ifdef([PKG_CHECK_MODULES],[
-       PKG_CHECK_MODULES([QTPLATFORM], [Qt5PlatformSupport], [QT_LIBS="$QTPLATFORM_LIBS $QT_LIBS"])
-       if test "x$TARGET_OS" = xlinux; then
-         PKG_CHECK_MODULES([X11XCB], [x11-xcb], [QT_LIBS="$X11XCB_LIBS $QT_LIBS"])
-         if ${PKG_CONFIG} --exists "Qt5Core >= 5.5" 2>/dev/null; then
-           PKG_CHECK_MODULES([QTXCBQPA], [Qt5XcbQpa], [QT_LIBS="$QTXCBQPA_LIBS $QT_LIBS"])
-         fi
-       elif test "x$TARGET_OS" = xdarwin; then
-         PKG_CHECK_MODULES([QTPRINT], [Qt5PrintSupport], [QT_LIBS="$QTPRINT_LIBS $QT_LIBS"])
+    fi
+   if test "x$use_pkgconfig" = xyes; then
+   : dnl
+   m4_ifdef([PKG_CHECK_MODULES],[
+     PKG_CHECK_MODULES([QTPLATFORM], [Qt5PlatformSupport], [QT_LIBS="$QTPLATFORM_LIBS $QT_LIBS"])
+     if test "x$TARGET_OS" = xlinux; then
+       PKG_CHECK_MODULES([X11XCB], [x11-xcb], [QT_LIBS="$X11XCB_LIBS $QT_LIBS"])
+       if ${PKG_CONFIG} --exists "Qt5Core >= 5.5" 2>/dev/null; then
+         PKG_CHECK_MODULES([QTXCBQPA], [Qt5XcbQpa], [QT_LIBS="$QTXCBQPA_LIBS $QT_LIBS"])
       fi
-     ])
-     else
-       if test "x$TARGET_OS" = xwindows; then
-         AC_CACHE_CHECK(for Qt >= 5.6, bitcoin_cv_need_platformsupport,[
-           AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
-               #include <QtCore/qconfig.h>
-               #ifndef QT_VERSION
-               #  include <QtCore/qglobal.h>
-               #endif
-             ]],
-             [[
-               #if QT_VERSION < 0x050600
-               choke
-               #endif
-             ]])],
-           [bitcoin_cv_need_platformsupport=yes],
-           [bitcoin_cv_need_platformsupport=no])
-         ])
-         if test "x$bitcoin_cv_need_platformsupport" = xyes; then
-           BITCOIN_QT_CHECK(AC_CHECK_LIB([${QT_LIB_PREFIX}PlatformSupport],[main],,BITCOIN_QT_FAIL(lib${QT_LIB_PREFIX}PlatformSupport not found)))
-         fi
+     elif test "x$TARGET_OS" = xdarwin; then
+       PKG_CHECK_MODULES([QTPRINT], [Qt5PrintSupport], [QT_LIBS="$QTPRINT_LIBS $QT_LIBS"])
+     fi
+   ])
+   else
+     if test "x$TARGET_OS" = xwindows; then
+       AC_CACHE_CHECK(for Qt >= 5.6, bitcoin_cv_need_platformsupport,[
+         AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
+             #include <QtCore/qconfig.h>
+             #ifndef QT_VERSION
+             #  include <QtCore/qglobal.h>
+             #endif
+           ]],
+           [[
+             #if QT_VERSION < 0x050600
+             choke
+             #endif
+           ]])],
+         [bitcoin_cv_need_platformsupport=yes],
+         [bitcoin_cv_need_platformsupport=no])
+       ])
+       if test "x$bitcoin_cv_need_platformsupport" = xyes; then
+         BITCOIN_QT_CHECK(AC_CHECK_LIB([${QT_LIB_PREFIX}PlatformSupport],[main],,BITCOIN_QT_FAIL(lib${QT_LIB_PREFIX}PlatformSupport not found)))
       fi
     fi
-  else
-    if test "x$qt_plugin_path" != x; then
-      QT_LIBS="$QT_LIBS -L$qt_plugin_path/accessible"
-      QT_LIBS="$QT_LIBS -L$qt_plugin_path/codecs"
-    fi
-  fi
+   fi
 ])

 dnl Internal. Find Qt libraries using pkg-config.
@ -406,38 +382,14 @@ dnl         first.
 dnl Inputs: $1: If bitcoin_qt_want_version is "auto", check for this version
 dnl         first.
 dnl Outputs: All necessary QT_* variables are set.
-dnl Outputs: bitcoin_qt_got_major_vers is set to "4" or "5".
 dnl Outputs: have_qt_test and have_qt_dbus are set (if applicable) to yes|no.
 AC_DEFUN([_BITCOIN_QT_FIND_LIBS_WITH_PKGCONFIG],[
  m4_ifdef([PKG_CHECK_MODULES],[
-  auto_priority_version=$1
-  if test "x$auto_priority_version" = x; then
-    auto_priority_version=qt5
-  fi
-    if test "x$bitcoin_qt_want_version" = xqt5 ||  ( test "x$bitcoin_qt_want_version" = xauto && test "x$auto_priority_version" = xqt5 ); then
-      QT_LIB_PREFIX=Qt5
-      bitcoin_qt_got_major_vers=5
-    else
-      QT_LIB_PREFIX=Qt
-      bitcoin_qt_got_major_vers=4
-    fi
+    QT_LIB_PREFIX=Qt5
    qt5_modules="Qt5Core Qt5Gui Qt5Network Qt5Widgets"
-    qt4_modules="QtCore QtGui QtNetwork"
    BITCOIN_QT_CHECK([
-      if test "x$bitcoin_qt_want_version" = xqt5 || ( test "x$bitcoin_qt_want_version" = xauto && test "x$auto_priority_version" = xqt5 ); then
-        PKG_CHECK_MODULES([QT5], [$qt5_modules], [QT_INCLUDES="$QT5_CFLAGS"; QT_LIBS="$QT5_LIBS" have_qt=yes],[have_qt=no])
-      elif test "x$bitcoin_qt_want_version" = xqt4 || ( test "x$bitcoin_qt_want_version" = xauto && test "x$auto_priority_version" = xqt4 ); then
-        PKG_CHECK_MODULES([QT4], [$qt4_modules], [QT_INCLUDES="$QT4_CFLAGS"; QT_LIBS="$QT4_LIBS" ; have_qt=yes], [have_qt=no])
-      fi
+      PKG_CHECK_MODULES([QT5], [$qt5_modules], [QT_INCLUDES="$QT5_CFLAGS"; QT_LIBS="$QT5_LIBS" have_qt=yes],[have_qt=no])

-      dnl qt version is set to 'auto' and the preferred version wasn't found. Now try the other.
-      if test "x$have_qt" = xno && test "x$bitcoin_qt_want_version" = xauto; then
-        if test "x$auto_priority_version" = xqt5; then
-          PKG_CHECK_MODULES([QT4], [$qt4_modules], [QT_INCLUDES="$QT4_CFLAGS"; QT_LIBS="$QT4_LIBS" ; have_qt=yes; QT_LIB_PREFIX=Qt; bitcoin_qt_got_major_vers=4], [have_qt=no])
-        else
-          PKG_CHECK_MODULES([QT5], [$qt5_modules], [QT_INCLUDES="$QT5_CFLAGS"; QT_LIBS="$QT5_LIBS" ; have_qt=yes; QT_LIB_PREFIX=Qt5; bitcoin_qt_got_major_vers=5], [have_qt=no])
-        fi
-      fi
      if test "x$have_qt" != xyes; then
        have_qt=no
        BITCOIN_QT_FAIL([Qt dependencies not found])
@ -458,7 +410,6 @@ dnl from the discovered headers.
 dnl Inputs: bitcoin_qt_want_version (from --with-gui=). The version to use.
 dnl         If "auto", the version will be discovered by _BITCOIN_QT_CHECK_QT5.
 dnl Outputs: All necessary QT_* variables are set.
-dnl Outputs: bitcoin_qt_got_major_vers is set to "4" or "5".
 dnl Outputs: have_qt_test and have_qt_dbus are set (if applicable) to yes|no.
 AC_DEFUN([_BITCOIN_QT_FIND_LIBS_WITHOUT_PKGCONFIG],[
  TEMP_CPPFLAGS="$CPPFLAGS"
@ -480,13 +431,7 @@ AC_DEFUN([_BITCOIN_QT_FIND_LIBS_WITHOUT_PKGCONFIG],[
    if test "x$bitcoin_qt_want_version" = xauto; then
      _BITCOIN_QT_CHECK_QT5
    fi
-    if test "x$bitcoin_cv_qt5" = xyes || test "x$bitcoin_qt_want_version" = xqt5; then
-      QT_LIB_PREFIX=Qt5
-      bitcoin_qt_got_major_vers=5
-    else
-      QT_LIB_PREFIX=Qt
-      bitcoin_qt_got_major_vers=4
-    fi
+    QT_LIB_PREFIX=Qt5
  ])

  BITCOIN_QT_CHECK([
@ -508,9 +453,7 @@ AC_DEFUN([_BITCOIN_QT_FIND_LIBS_WITHOUT_PKGCONFIG],[
  BITCOIN_QT_CHECK(AC_CHECK_LIB([${QT_LIB_PREFIX}Core]   ,[main],,BITCOIN_QT_FAIL(lib${QT_LIB_PREFIX}Core not found)))
  BITCOIN_QT_CHECK(AC_CHECK_LIB([${QT_LIB_PREFIX}Gui]    ,[main],,BITCOIN_QT_FAIL(lib${QT_LIB_PREFIX}Gui not found)))
  BITCOIN_QT_CHECK(AC_CHECK_LIB([${QT_LIB_PREFIX}Network],[main],,BITCOIN_QT_FAIL(lib${QT_LIB_PREFIX}Network not found)))
-  if test "x$bitcoin_qt_got_major_vers" = x5; then
-    BITCOIN_QT_CHECK(AC_CHECK_LIB([${QT_LIB_PREFIX}Widgets],[main],,BITCOIN_QT_FAIL(lib${QT_LIB_PREFIX}Widgets not found)))
-  fi
+  BITCOIN_QT_CHECK(AC_CHECK_LIB([${QT_LIB_PREFIX}Widgets],[main],,BITCOIN_QT_FAIL(lib${QT_LIB_PREFIX}Widgets not found)))
  QT_LIBS="$LIBS"
  LIBS="$TEMP_LIBS"

--- a/configure.ac
+++ b/configure.ac
@ -837,7 +837,7 @@ fi
 BITCOIN_QT_INIT

 dnl sets $bitcoin_enable_qt, $bitcoin_enable_qt_test, $bitcoin_enable_qt_dbus
-BITCOIN_QT_CONFIGURE([$use_pkgconfig], [qt5])
+BITCOIN_QT_CONFIGURE([$use_pkgconfig])

 if test x$build_bitcoin_utils$build_bitcoind$bitcoin_enable_qt$use_tests$use_bench = xnonononono; then
    use_boost=no
@ -1422,7 +1422,6 @@ echo "Options used to compile and link:"
 echo "  with wallet   = $enable_wallet"
 echo "  with gui / qt = $bitcoin_enable_qt"
 if test x$bitcoin_enable_qt != xno; then
-    echo "    qt version  = $bitcoin_qt_got_major_vers"
    echo "    with qr     = $use_qr"
 fi
 echo "  with zmq      = $use_zmq"
--- a/doc/build-osx.md
+++ b/doc/build-osx.md
@ -24,8 +24,6 @@ If you want to build the disk image with `make deploy` (.dmg / optional), you ne

    brew install librsvg

-NOTE: Building with Qt4 is still supported, however, could result in a broken UI. Building with Qt5 is recommended.
-
 Berkeley DB
 -----------
 It is recommended to use Berkeley DB 4.8. If you have to build it yourself,
--- a/doc/build-unix.md
+++ b/doc/build-unix.md
@ -100,18 +100,13 @@ ZMQ dependencies (provides ZMQ API 4.x):
 #### Dependencies for the GUI

 If you want to build Bitcoin-Qt, make sure that the required packages for Qt development
-are installed. Either Qt 5 or Qt 4 are necessary to build the GUI.
-If both Qt 4 and Qt 5 are installed, Qt 5 will be used. Pass `--with-gui=qt4` to configure to choose Qt4.
+are installed. Qt 5 is necessary to build the GUI.
 To build without GUI pass `--without-gui`.

-To build with Qt 5 (recommended) you need the following:
+To build with Qt 5 you need the following:

    sudo apt-get install libqt5gui5 libqt5core5a libqt5dbus5 qttools5-dev qttools5-dev-tools libprotobuf-dev protobuf-compiler

-Alternatively, to build with Qt 4 you need the following:
-
-    sudo apt-get install libqt4-dev libprotobuf-dev protobuf-compiler
-
 libqrencode (optional) can be installed with:

    sudo apt-get install libqrencode-dev
@ -132,7 +127,7 @@ Optional:

    sudo dnf install miniupnpc-devel

-To build with Qt 5 (recommended) you need the following:
+To build with Qt 5 you need the following:

    sudo dnf install qt5-qttools-devel qt5-qtbase-devel protobuf-devel

--- a/doc/dependencies.md
+++ b/doc/dependencies.md
@ -23,7 +23,7 @@ These are the dependencies currently used by Bitcoin Core. You can find instruct
 | protobuf | [2.6.3](https://github.com/google/protobuf/releases) |  | No |  |  |
 | Python (tests) |  | [3.4](https://www.python.org/downloads) |  |  |  |
 | qrencode | [3.4.4](https://fukuchi.org/works/qrencode) |  | No |  |  |
-| Qt | [5.7.1](https://download.qt.io/official_releases/qt/) | 4.7+ | No |  |  |
+| Qt | [5.7.1](https://download.qt.io/official_releases/qt/) | 5.x | No |  |  |
 | XCB |  |  |  |  | [Yes](https://github.com/bitcoin/bitcoin/blob/master/depends/packages/qt.mk#L94) (Linux only) |
 | xkbcommon |  |  |  |  | [Yes](https://github.com/bitcoin/bitcoin/blob/master/depends/packages/qt.mk#L93) (Linux only) |
 | ZeroMQ | [4.2.3](https://github.com/zeromq/libzmq/releases) |  | No |  |  |
--- a/src/qt/README.md
+++ b/src/qt/README.md
@ -1,6 +1,6 @@
 This directory contains the BitcoinQT graphical user interface (GUI). It uses the cross-platform framework [Qt](https://www1.qt.io/developers/).

-The current precise version for Qt 5 is specified in [qt.mk](/depends/packages/qt.mk). Qt 4 is also supported (see [#8263](https://github.com/bitcoin/bitcoin/issues/8263)).
+The current precise version for Qt 5 is specified in [qt.mk](/depends/packages/qt.mk).

 ## Compile and run

@ -16,7 +16,7 @@ To run:

 ### forms

-Contains [Designer UI](http://doc.qt.io/qt-5.9/designer-using-a-ui-file.html) files. They are created with [Qt Creator](#using-qt-creator-as-ide), but can be edited using any text editor.
+Contains [Designer UI](https://doc.qt.io/qt-5.9/designer-using-a-ui-file.html) files. They are created with [Qt Creator](#using-qt-creator-as-ide), but can be edited using any text editor.

 ### locale

@ -36,7 +36,7 @@ Represents the main window of the Bitcoin UI.

 ### \*model.(h/cpp)

-The model. When it has a corresponding controller, it generally inherits from  [QAbstractTableModel](http://doc.qt.io/qt-5/qabstracttablemodel.html). Models that are used by controllers as helpers inherit from other Qt classes like [QValidator](http://doc.qt.io/qt-5/qvalidator.html).
+The model. When it has a corresponding controller, it generally inherits from  [QAbstractTableModel](https://doc.qt.io/qt-5/qabstracttablemodel.html). Models that are used by controllers as helpers inherit from other Qt classes like [QValidator](https://doc.qt.io/qt-5/qvalidator.html).

 ClientModel is used by the main application `bitcoingui` and several models like `peertablemodel`.

@ -46,7 +46,7 @@ A controller. `:NAMEpage.cpp` generally includes `:NAMEmodel.h` and `forms/:NAME

 ### \*dialog.(h/cpp)

-Various dialogs, e.g. to open a URL. Inherit from [QDialog](http://doc.qt.io/qt-4.8/qdialog.html).
+Various dialogs, e.g. to open a URL. Inherit from [QDialog](https://doc.qt.io/qt-5/qdialog.html).

 ### paymentserver.(h/cpp)

--- a/src/qt/addressbookpage.cpp
+++ b/src/qt/addressbookpage.cpp
@ -160,13 +160,8 @@ void AddressBookPage::setModel(AddressTableModel *_model)
    ui->tableView->sortByColumn(0, Qt::AscendingOrder);

    // Set column widths
-#if QT_VERSION < 0x050000
-    ui->tableView->horizontalHeader()->setResizeMode(AddressTableModel::Label, QHeaderView::Stretch);
-    ui->tableView->horizontalHeader()->setResizeMode(AddressTableModel::Address, QHeaderView::ResizeToContents);
-#else
    ui->tableView->horizontalHeader()->setSectionResizeMode(AddressTableModel::Label, QHeaderView::Stretch);
    ui->tableView->horizontalHeader()->setSectionResizeMode(AddressTableModel::Address, QHeaderView::ResizeToContents);
-#endif

    connect(ui->tableView->selectionModel(), SIGNAL(selectionChanged(QItemSelection,QItemSelection)),
        this, SLOT(selectionChanged()));
--- a/src/qt/bantablemodel.cpp
+++ b/src/qt/bantablemodel.cpp
@ -52,9 +52,7 @@ public:
        node.getBanned(banMap);

        cachedBanlist.clear();
-#if QT_VERSION >= 0x040700
        cachedBanlist.reserve(banMap.size());
-#endif
        for (const auto& entry : banMap)
        {
            CCombinedBan banEntry;
--- a/src/qt/bitcoin.cpp
+++ b/src/qt/bitcoin.cpp
@ -55,13 +55,6 @@

 #if defined(QT_STATICPLUGIN)
 #include <QtPlugin>
-#if QT_VERSION < 0x050000
-Q_IMPORT_PLUGIN(qcncodecs)
-Q_IMPORT_PLUGIN(qjpcodecs)
-Q_IMPORT_PLUGIN(qtwcodecs)
-Q_IMPORT_PLUGIN(qkrcodecs)
-Q_IMPORT_PLUGIN(qtaccessiblewidgets)
-#else
 #if QT_VERSION < 0x050400
 Q_IMPORT_PLUGIN(AccessibleFactory)
 #endif
@ -73,11 +66,6 @@ Q_IMPORT_PLUGIN(QWindowsIntegrationPlugin);
 Q_IMPORT_PLUGIN(QCocoaIntegrationPlugin);
 #endif
 #endif
-#endif
-
-#if QT_VERSION < 0x050000
-#include <QTextCodec>
-#endif

 // Declare meta types used for QMetaObject::invokeMethod
 Q_DECLARE_METATYPE(bool*)
@ -151,16 +139,6 @@ static void initTranslations(QTranslator &qtTranslatorBase, QTranslator &qtTrans
 }

 /* qDebug() message handler --> debug.log */
-#if QT_VERSION < 0x050000
-void DebugMessageHandler(QtMsgType type, const char *msg)
-{
-    if (type == QtDebugMsg) {
-        LogPrint(BCLog::QT, "GUI: %s\n", msg);
-    } else {
-        LogPrintf("GUI: %s\n", msg);
-    }
-}
-#else
 void DebugMessageHandler(QtMsgType type, const QMessageLogContext& context, const QString &msg)
 {
    Q_UNUSED(context);
@ -170,7 +148,6 @@ void DebugMessageHandler(QtMsgType type, const QMessageLogContext& context, cons
        LogPrintf("GUI: %s\n", msg.toStdString());
    }
 }
-#endif

 /** Class encapsulating Bitcoin Core startup and shutdown.
 * Allows running startup and shutdown in a different thread from the UI thread.
@ -586,12 +563,6 @@ int main(int argc, char *argv[])
    // Do not refer to data directory yet, this can be overridden by Intro::pickDataDirectory

    /// 1. Basic Qt initialization (not dependent on parameters or configuration)
-#if QT_VERSION < 0x050000
-    // Internal string conversion is all UTF-8
-    QTextCodec::setCodecForTr(QTextCodec::codecForName("UTF-8"));
-    QTextCodec::setCodecForCStrings(QTextCodec::codecForTr());
-#endif
-
    Q_INIT_RESOURCE(bitcoin);
    Q_INIT_RESOURCE(bitcoin_locale);

@ -722,17 +693,12 @@ int main(int argc, char *argv[])
    /// 9. Main GUI initialization
    // Install global event filter that makes sure that long tooltips can be word-wrapped
    app.installEventFilter(new GUIUtil::ToolTipToRichTextFilter(TOOLTIP_WRAP_THRESHOLD, &app));
-#if QT_VERSION < 0x050000
-    // Install qDebug() message handler to route to debug.log
-    qInstallMsgHandler(DebugMessageHandler);
-#else
 #if defined(Q_OS_WIN)
    // Install global event filter for processing Windows session related Windows messages (WM_QUERYENDSESSION and WM_ENDSESSION)
    qApp->installNativeEventFilter(new WinShutdownMonitor());
 #endif
    // Install qDebug() message handler to route to debug.log
    qInstallMessageHandler(DebugMessageHandler);
-#endif
    // Allow parameter interaction before we create the options model
    app.parameterSetup();
    // Load GUI settings from QSettings
@ -753,7 +719,7 @@ int main(int argc, char *argv[])
        // so the GUI thread won't be held up.
        if (node->baseInitialize()) {
            app.requestInitialize();
-#if defined(Q_OS_WIN) && QT_VERSION >= 0x050000
+#if defined(Q_OS_WIN)
            WinShutdownMonitor::registerShutdownBlockReason(QObject::tr("%1 didn't yet exit safely...").arg(QObject::tr(PACKAGE_NAME)), (HWND)app.getMainWinId());
 #endif
            app.exec();
--- a/src/qt/bitcoingui.cpp
+++ b/src/qt/bitcoingui.cpp
@ -55,14 +55,8 @@
 #include <QStyle>
 #include <QTimer>
 #include <QToolBar>
-#include <QVBoxLayout>
-
-#if QT_VERSION < 0x050000
-#include <QTextDocument>
-#include <QUrl>
-#else
 #include <QUrlQuery>
-#endif
+#include <QVBoxLayout>

 const std::string BitcoinGUI::DEFAULT_UIPLATFORM =
 #if defined(Q_OS_MAC)
@ -148,12 +142,6 @@ BitcoinGUI::BitcoinGUI(interfaces::Node& node, const PlatformStyle *_platformSty
 #endif
    setWindowTitle(windowTitle);

-#if defined(Q_OS_MAC) && QT_VERSION < 0x050000
-    // This property is not implemented in Qt 5. Setting it has no effect.
-    // A replacement API (QtMacUnifiedToolBar) is available in QtMacExtras.
-    setUnifiedTitleAndToolBarOnMac(true);
-#endif
-
    rpcConsole = new RPCConsole(node, _platformStyle, 0);
    helpMessageDialog = new HelpMessageDialog(node, this, false);
 #ifdef ENABLE_WALLET
@ -230,7 +218,7 @@ BitcoinGUI::BitcoinGUI(interfaces::Node& node, const PlatformStyle *_platformSty

    // Override style sheet for progress bar for styles that have a segmented progress bar,
    // as they make the text unreadable (workaround for issue #1071)
-    // See https://qt-project.org/doc/qt-4.8/gallery.html
+    // See https://doc.qt.io/qt-5/gallery.html
    QString curStyle = QApplication::style()->metaObject()->className();
    if(curStyle == "QWindowsStyle" || curStyle == "QWindowsXPStyle")
    {
--- a/src/qt/coincontroldialog.cpp
+++ b/src/qt/coincontroldialog.cpp
@ -109,11 +109,7 @@ CoinControlDialog::CoinControlDialog(const PlatformStyle *_platformStyle, QWidge
    connect(ui->treeWidget, SIGNAL(itemChanged(QTreeWidgetItem*, int)), this, SLOT(viewItemChanged(QTreeWidgetItem*, int)));

    // click on header
-#if QT_VERSION < 0x050000
-    ui->treeWidget->header()->setClickable(true);
-#else
    ui->treeWidget->header()->setSectionsClickable(true);
-#endif
    connect(ui->treeWidget->header(), SIGNAL(sectionClicked(int)), this, SLOT(headerSectionClicked(int)));

    // ok button
@ -392,13 +388,11 @@ void CoinControlDialog::viewItemChanged(QTreeWidgetItem* item, int column)

    // TODO: Remove this temporary qt5 fix after Qt5.3 and Qt5.4 are no longer used.
    //       Fixed in Qt5.5 and above: https://bugreports.qt.io/browse/QTBUG-43473
-#if QT_VERSION >= 0x050000
    else if (column == COLUMN_CHECKBOX && item->childCount() > 0)
    {
        if (item->checkState(COLUMN_CHECKBOX) == Qt::PartiallyChecked && item->child(0)->checkState(COLUMN_CHECKBOX) == Qt::PartiallyChecked)
            item->setCheckState(COLUMN_CHECKBOX, Qt::Checked);
    }
-#endif
 }

 // shows count of locked unspent outputs
--- a/src/qt/guiutil.cpp
+++ b/src/qt/guiutil.cpp
@ -53,13 +53,9 @@
 #include <QSettings>
 #include <QTextDocument> // for Qt::mightBeRichText
 #include <QThread>
+#include <QUrlQuery>
 #include <QMouseEvent>

-#if QT_VERSION < 0x050000
-#include <QUrl>
-#else
-#include <QUrlQuery>
-#endif

 #if QT_VERSION >= 0x50200
 #include <QFontDatabase>
@ -95,11 +91,7 @@ QFont fixedPitchFont()
    return QFontDatabase::systemFont(QFontDatabase::FixedFont);
 #else
    QFont font("Monospace");
-#if QT_VERSION >= 0x040800
    font.setStyleHint(QFont::Monospace);
-#else
-    font.setStyleHint(QFont::TypeWriter);
-#endif
    return font;
 #endif
 }
@ -127,12 +119,10 @@ void setupAddressWidget(QValidatedLineEdit *widget, QWidget *parent)
    parent->setFocusProxy(widget);

    widget->setFont(fixedPitchFont());
-#if QT_VERSION >= 0x040700
    // We don't want translators to use own addresses in translations
    // and this is the only place, where this address is supplied.
    widget->setPlaceholderText(QObject::tr("Enter a Bitcoin address (e.g. %1)").arg(
        QString::fromStdString(DummyAddress(Params()))));
-#endif
    widget->setValidator(new BitcoinAddressEntryValidator(parent));
    widget->setCheckValidator(new BitcoinAddressCheckValidator(parent));
 }
@ -151,12 +141,8 @@ bool parseBitcoinURI(const QUrl &uri, SendCoinsRecipient *out)
    }
    rv.amount = 0;

-#if QT_VERSION < 0x050000
-    QList<QPair<QString, QString> > items = uri.queryItems();
-#else
    QUrlQuery uriQuery(uri);
    QList<QPair<QString, QString> > items = uriQuery.queryItems();
-#endif
    for (QList<QPair<QString, QString> >::iterator i = items.begin(); i != items.end(); i++)
    {
        bool fShouldReturnFalse = false;
@ -242,11 +228,7 @@ bool isDust(interfaces::Node& node, const QString& address, const CAmount& amoun

 QString HtmlEscape(const QString& str, bool fMultiLine)
 {
-#if QT_VERSION < 0x050000
-    QString escaped = Qt::escape(str);
-#else
    QString escaped = str.toHtmlEscaped();
-#endif
    if(fMultiLine)
    {
        escaped = escaped.replace("\n", "<br>\n");
@ -287,11 +269,7 @@ QString getSaveFileName(QWidget *parent, const QString &caption, const QString &
    QString myDir;
    if(dir.isEmpty()) // Default to user documents location
    {
-#if QT_VERSION < 0x050000
-        myDir = QDesktopServices::storageLocation(QDesktopServices::DocumentsLocation);
-#else
        myDir = QStandardPaths::writableLocation(QStandardPaths::DocumentsLocation);
-#endif
    }
    else
    {
@ -337,11 +315,7 @@ QString getOpenFileName(QWidget *parent, const QString &caption, const QString &
    QString myDir;
    if(dir.isEmpty()) // Default to user documents location
    {
-#if QT_VERSION < 0x050000
-        myDir = QDesktopServices::storageLocation(QDesktopServices::DocumentsLocation);
-#else
        myDir = QStandardPaths::writableLocation(QStandardPaths::DocumentsLocation);
-#endif
    }
    else
    {
@ -495,11 +469,7 @@ void TableViewLastColumnResizingFixer::disconnectViewHeadersSignals()
 // Refactored here for readability.
 void TableViewLastColumnResizingFixer::setViewHeaderResizeMode(int logicalIndex, QHeaderView::ResizeMode resizeMode)
 {
-#if QT_VERSION < 0x050000
-    tableView->horizontalHeader()->setResizeMode(logicalIndex, resizeMode);
-#else
    tableView->horizontalHeader()->setSectionResizeMode(logicalIndex, resizeMode);
-#endif
 }

 void TableViewLastColumnResizingFixer::resizeColumn(int nColumnIndex, int width)
--- a/src/qt/guiutil.h
+++ b/src/qt/guiutil.h
@ -233,7 +233,7 @@ namespace GUIUtil
        void mouseReleaseEvent(QMouseEvent *event);
    };

-#if defined(Q_OS_MAC) && QT_VERSION >= 0x050000
+#if defined(Q_OS_MAC)
    // workaround for Qt OSX Bug:
    // https://bugreports.qt-project.org/browse/QTBUG-15631
    // QProgressBar uses around 10% CPU even when app is in background
--- a/src/qt/macdockiconhandler.mm
+++ b/src/qt/macdockiconhandler.mm
@ -14,10 +14,6 @@
 #include <objc/objc.h>
 #include <objc/message.h>

-#if QT_VERSION < 0x050000
-extern void qt_mac_set_dock_menu(QMenu *);
-#endif
-
 static MacDockIconHandler *s_instance = nullptr;

 bool dockClickHandler(id self,SEL _cmd,...) {
@ -54,9 +50,7 @@ MacDockIconHandler::MacDockIconHandler() : QObject()
    this->m_dummyWidget = new QWidget();
    this->m_dockMenu = new QMenu(this->m_dummyWidget);
    this->setMainWindow(nullptr);
-#if QT_VERSION < 0x050000
-    qt_mac_set_dock_menu(this->m_dockMenu);
-#elif QT_VERSION >= 0x050200
+#if QT_VERSION >= 0x050200
    this->m_dockMenu->setAsDockMenu();
 #endif
    [pool release];
--- a/src/qt/networkstyle.cpp
+++ b/src/qt/networkstyle.cpp
@ -68,11 +68,7 @@ NetworkStyle::NetworkStyle(const QString &_appName, const int iconColorHueShift,
        }

        //convert back to QPixmap
-#if QT_VERSION >= 0x040700
        pixmap.convertFromImage(img);
-#else
-        pixmap = QPixmap::fromImage(img);
-#endif
    }

    appIcon             = QIcon(pixmap);
--- a/src/qt/openuridialog.cpp
+++ b/src/qt/openuridialog.cpp
@ -15,9 +15,7 @@ OpenURIDialog::OpenURIDialog(QWidget *parent) :
    ui(new Ui::OpenURIDialog)
 {
    ui->setupUi(this);
-#if QT_VERSION >= 0x040700
    ui->uriEdit->setPlaceholderText("bitcoin:");
-#endif
 }

 OpenURIDialog::~OpenURIDialog()
--- a/src/qt/optionsdialog.cpp
+++ b/src/qt/optionsdialog.cpp
@ -97,28 +97,16 @@ OptionsDialog::OptionsDialog(QWidget *parent, bool enableWallet) :
        /** check if the locale name consists of 2 parts (language_country) */
        if(langStr.contains("_"))
        {
-#if QT_VERSION >= 0x040800
            /** display language strings as "native language - native country (locale name)", e.g. "Deutsch - Deutschland (de)" */
            ui->lang->addItem(locale.nativeLanguageName() + QString(" - ") + locale.nativeCountryName() + QString(" (") + langStr + QString(")"), QVariant(langStr));
-#else
-            /** display language strings as "language - country (locale name)", e.g. "German - Germany (de)" */
-            ui->lang->addItem(QLocale::languageToString(locale.language()) + QString(" - ") + QLocale::countryToString(locale.country()) + QString(" (") + langStr + QString(")"), QVariant(langStr));
-#endif
        }
        else
        {
-#if QT_VERSION >= 0x040800
            /** display language strings as "native language (locale name)", e.g. "Deutsch (de)" */
            ui->lang->addItem(locale.nativeLanguageName() + QString(" (") + langStr + QString(")"), QVariant(langStr));
-#else
-            /** display language strings as "language (locale name)", e.g. "German (de)" */
-            ui->lang->addItem(QLocale::languageToString(locale.language()) + QString(" (") + langStr + QString(")"), QVariant(langStr));
-#endif
        }
    }
-#if QT_VERSION >= 0x040700
    ui->thirdPartyTxUrls->setPlaceholderText("https://example.com/tx/%s");
-#endif

    ui->unit->setModel(new BitcoinUnits(this));

--- a/src/qt/paymentrequestplus.cpp
+++ b/src/qt/paymentrequestplus.cpp
@ -97,12 +97,10 @@ bool PaymentRequestPlus::getMerchant(X509_STORE* certStore, QString& merchant) c
            qWarning() << "PaymentRequestPlus::getMerchant: Payment request: certificate expired or not yet active: " << qCert;
            return false;
        }
-#if QT_VERSION >= 0x050000
        if (qCert.isBlacklisted()) {
            qWarning() << "PaymentRequestPlus::getMerchant: Payment request: certificate blacklisted: " << qCert;
            return false;
        }
-#endif
        const unsigned char *data = (const unsigned char *)certChain.certificate(i).data();
        X509 *cert = d2i_X509(nullptr, &data, certChain.certificate(i).size());
        if (cert)
--- a/src/qt/paymentserver.cpp
+++ b/src/qt/paymentserver.cpp
@ -41,12 +41,7 @@
 #include <QSslSocket>
 #include <QStringList>
 #include <QTextDocument>
-
-#if QT_VERSION < 0x050000
-#include <QUrl>
-#else
 #include <QUrlQuery>
-#endif

 const int BITCOIN_IPC_CONNECT_TIMEOUT = 1000; // milliseconds
 const QString BITCOIN_IPC_PREFIX("bitcoin:");
@ -100,11 +95,7 @@ static QList<QString> savedPaymentRequests;

 static void ReportInvalidCertificate(const QSslCertificate& cert)
 {
-#if QT_VERSION < 0x050000
-    qDebug() << QString("%1: Payment server found an invalid certificate: ").arg(__func__) << cert.serialNumber() << cert.subjectInfo(QSslCertificate::CommonName) << cert.subjectInfo(QSslCertificate::OrganizationalUnitName);
-#else
    qDebug() << QString("%1: Payment server found an invalid certificate: ").arg(__func__) << cert.serialNumber() << cert.subjectInfo(QSslCertificate::CommonName) << cert.subjectInfo(QSslCertificate::DistinguishedNameQualifier) << cert.subjectInfo(QSslCertificate::OrganizationalUnitName);
-#endif
 }

 //
@ -157,13 +148,11 @@ void PaymentServer::LoadRootCAs(X509_STORE* _store)
            continue;
        }

-#if QT_VERSION >= 0x050000
        // Blacklisted certificate
        if (cert.isBlacklisted()) {
            ReportInvalidCertificate(cert);
            continue;
        }
-#endif
        QByteArray certData = cert.toDer();
        const unsigned char *data = (const unsigned char *)certData.data();

@ -413,11 +402,7 @@ void PaymentServer::handleURIOrFile(const QString& s)
    }
    else if (s.startsWith(BITCOIN_IPC_PREFIX, Qt::CaseInsensitive)) // bitcoin: URI
    {
-#if QT_VERSION < 0x050000
-        QUrl uri(s);
-#else
        QUrlQuery uri((QUrl(s)));
-#endif
        if (uri.hasQueryItem("r")) // payment request URI
        {
            QByteArray temp;
--- a/src/qt/peertablemodel.cpp
+++ b/src/qt/peertablemodel.cpp
@ -64,9 +64,7 @@ public:

            interfaces::Node::NodesStats nodes_stats;
            node.getNodesStats(nodes_stats);
-#if QT_VERSION >= 0x040700
            cachedNodeStats.reserve(nodes_stats.size());
-#endif
            for (auto& node_stats : nodes_stats)
            {
                CNodeCombinedStats stats;
--- a/src/qt/receiverequestdialog.cpp
+++ b/src/qt/receiverequestdialog.cpp
@ -16,9 +16,6 @@
 #include <QMimeData>
 #include <QMouseEvent>
 #include <QPixmap>
-#if QT_VERSION < 0x050000
-#include <QUrl>
-#endif

 #if defined(HAVE_CONFIG_H)
 #include <config/bitcoin-config.h> /* for USE_QRCODE */
--- a/src/qt/rpcconsole.cpp
+++ b/src/qt/rpcconsole.cpp
@ -40,10 +40,6 @@
 #include <QTimer>
 #include <QStringList>

-#if QT_VERSION < 0x050000
-#include <QUrl>
-#endif
-
 // TODO: add a scrollback limit, as there is currently none
 // TODO: make it possible to filter out categories (esp debug messages when implemented)
 // TODO: receive errors and debug messages through ClientModel
--- a/src/qt/sendcoinsentry.cpp
+++ b/src/qt/sendcoinsentry.cpp
@ -32,9 +32,7 @@ SendCoinsEntry::SendCoinsEntry(const PlatformStyle *_platformStyle, QWidget *par

    if (platformStyle->getUseExtraSpacing())
        ui->payToLayout->setSpacing(4);
-#if QT_VERSION >= 0x040700
    ui->addAsLabel->setPlaceholderText(tr("Enter a label for this address to add it to your address book"));
-#endif

    // normal bitcoin address field
    GUIUtil::setupAddressWidget(ui->payTo, this);
--- a/src/qt/signverifymessagedialog.cpp
+++ b/src/qt/signverifymessagedialog.cpp
@ -37,9 +37,7 @@ SignVerifyMessageDialog::SignVerifyMessageDialog(const PlatformStyle *_platformS
    ui->verifyMessageButton_VM->setIcon(platformStyle->SingleColorIcon(":/icons/transaction_0"));
    ui->clearButton_VM->setIcon(platformStyle->SingleColorIcon(":/icons/remove"));

-#if QT_VERSION >= 0x040700
    ui->signatureOut_SM->setPlaceholderText(tr("Click \"Sign Message\" to generate signature"));
-#endif

    GUIUtil::setupAddressWidget(ui->addressIn_SM, this);
    GUIUtil::setupAddressWidget(ui->addressIn_VM, this);
--- a/src/qt/test/test_main.cpp
+++ b/src/qt/test/test_main.cpp
@ -26,12 +26,6 @@

 #if defined(QT_STATICPLUGIN)
 #include <QtPlugin>
-#if QT_VERSION < 0x050000
-Q_IMPORT_PLUGIN(qcncodecs)
-Q_IMPORT_PLUGIN(qjpcodecs)
-Q_IMPORT_PLUGIN(qtwcodecs)
-Q_IMPORT_PLUGIN(qkrcodecs)
-#else
 #if defined(QT_QPA_PLATFORM_MINIMAL)
 Q_IMPORT_PLUGIN(QMinimalIntegrationPlugin);
 #endif
@ -43,7 +37,6 @@ Q_IMPORT_PLUGIN(QWindowsIntegrationPlugin);
 Q_IMPORT_PLUGIN(QCocoaIntegrationPlugin);
 #endif
 #endif
-#endif

 extern void noui_connect();

--- a/src/qt/test/wallettests.cpp
+++ b/src/qt/test/wallettests.cpp
@ -87,17 +87,6 @@ QModelIndex FindTx(const QAbstractItemModel& model, const uint256& txid)
    return {};
 }

-//! Request context menu (call method that is public in qt5, but protected in qt4).
-void RequestContextMenu(QWidget* widget)
-{
-    class Qt4Hack : public QWidget
-    {
-    public:
-        using QWidget::customContextMenuRequested;
-    };
-    static_cast<Qt4Hack*>(widget)->customContextMenuRequested({});
-}
-
 //! Invoke bumpfee on txid and check results.
 void BumpFee(TransactionView& view, const uint256& txid, bool expectDisabled, std::string expectError, bool cancel)
 {
@ -110,7 +99,7 @@ void BumpFee(TransactionView& view, const uint256& txid, bool expectDisabled, st
    QAction* action = view.findChild<QAction*>("bumpFeeAction");
    table->selectionModel()->select(index, QItemSelectionModel::ClearAndSelect | QItemSelectionModel::Rows);
    action->setEnabled(expectDisabled);
-    RequestContextMenu(table);
+    table->customContextMenuRequested({});
    QCOMPARE(action->isEnabled(), !expectDisabled);

    action->setEnabled(true);
--- a/src/qt/transactionview.cpp
+++ b/src/qt/transactionview.cpp
@ -95,15 +95,11 @@ TransactionView::TransactionView(const PlatformStyle *platformStyle, QWidget *pa
    hlayout->addWidget(typeWidget);

    search_widget = new QLineEdit(this);
-#if QT_VERSION >= 0x040700
    search_widget->setPlaceholderText(tr("Enter address, transaction id, or label to search"));
-#endif
    hlayout->addWidget(search_widget);

    amountWidget = new QLineEdit(this);
-#if QT_VERSION >= 0x040700
    amountWidget->setPlaceholderText(tr("Min amount"));
-#endif
    if (platformStyle->getUseExtraSpacing()) {
        amountWidget->setFixedWidth(97);
    } else {
--- a/src/qt/winshutdownmonitor.cpp
+++ b/src/qt/winshutdownmonitor.cpp
@ -4,7 +4,7 @@

 #include <qt/winshutdownmonitor.h>

-#if defined(Q_OS_WIN) && QT_VERSION >= 0x050000
+#if defined(Q_OS_WIN)
 #include <init.h>
 #include <util.h>

--- a/src/qt/winshutdownmonitor.h
+++ b/src/qt/winshutdownmonitor.h
@ -9,7 +9,6 @@
 #include <QByteArray>
 #include <QString>

-#if QT_VERSION >= 0x050000
 #include <windef.h> // for HWND

 #include <QAbstractNativeEventFilter>
@ -24,6 +23,5 @@ public:
    static void registerShutdownBlockReason(const QString& strReason, const HWND& mainWinId);
 };
 #endif
-#endif

 #endif // BITCOIN_QT_WINSHUTDOWNMONITOR_H