qt: add 5.8.0 which builds on Sierra with clang 8.1.0 (#4109)

* qt: add 5.8.0 which builds on Sierra with clang 8.1.0

* enable parallel build, add freetype dependency

* minor

* minor

var/spack/repos/builtin/packages/qt/QTBUG-57656.patch

@@ -0,0 +1,17 @@
+diff --git a/mkspecs/features/qt_module.prf b/mkspecs/features/qt_module.prf
+index f6cbf99..ec31e45 100644
+--- a/qtbase/mkspecs/features/qt_module.prf
++++ b/qtbase/mkspecs/features/qt_module.prf
+@@ -68,9 +68,9 @@ load(qt_build_paths)
+ 
+ header_module {
+     TEMPLATE     = aux
+-    CONFIG      += \
+-        force_qt \  # Needed for the headers_clean tests.
+-        qt_no_install_library
++    CONFIG      += force_qt  # Needed for the headers_clean tests.
++    !lib_bundle: \
++        CONFIG  += qt_no_install_library
+ } else {
+     TEMPLATE     = lib
+ }

var/spack/repos/builtin/packages/qt/QTBUG-58038.patch

@@ -0,0 +1,12 @@
+diff --git a/qtbase/src/3rdparty/freetype/freetype.pro b/qtbase/src/3rdparty/freetype/freetype.pro
+index 5b1eb92..390a6da 100644
+--- a/qtbase/src/3rdparty/freetype/freetype.pro
++++ b/qtbase/src/3rdparty/freetype/freetype.pro
+@@ -69,6 +69,7 @@ DEFINES += FT_CONFIG_OPTION_SYSTEM_ZLIB
+ include(../zlib_dependency.pri)
+
+ DEFINES += FT_CONFIG_OPTION_USE_PNG
++include($$OUT_PWD/../../gui/qtgui-config.pri)
+ QMAKE_USE_PRIVATE += libpng
+
+ DEFINES += TT_CONFIG_OPTION_SUBPIXEL_HINTING

var/spack/repos/builtin/packages/qt/package.py

@@ -35,6 +35,7 @@ class Qt(Package):
     list_url = 'http://download.qt.io/archive/qt/'
     list_depth = 3
 
+    version('5.8.0',  'a9f2494f75f966e2f22358ec367d8f41')
     version('5.7.1',  '031fb3fd0c3cc0f1082644492683f18d')
     version('5.7.0',  '9a46cce61fc64c20c3ac0a0e0fa41b42')
     version('5.5.1',  '59f0216819152b77536cf660b015d784')
@@ -64,6 +65,11 @@ class Qt(Package):
 
     patch('qt3krell.patch', when='@3.3.8b+krellpatch')
 
+    # see https://bugreports.qt.io/browse/QTBUG-57656
+    patch('QTBUG-57656.patch', when='@5.8.0')
+    # see https://bugreports.qt.io/browse/QTBUG-58038
+    patch('QTBUG-58038.patch', when='@5.8.0')
+
     # https://github.com/xboxdrv/xboxdrv/issues/188
     patch('btn_trigger_happy.patch', when='@5.7.0:')
 
@@ -84,6 +90,10 @@ class Qt(Package):
     depends_on("libmng")
     depends_on("jpeg")
     depends_on("icu4c")
+    # FIXME:
+    # depends_on("freetype", when='@5.8:') and '-system-freetype'
+    # -system-harfbuzz
+    # -system-pcre
 
     # QtQml
     depends_on("python", when='@5.7.0:', type='build')
@@ -185,10 +195,19 @@ def common_config_args(self):
             '-confirm-license',
             '-openssl-linked',
             '-optimized-qmake',
-            '-no-openvg',
-            '-no-pch',
+            '-no-pch'
         ]
 
+        if '@:5.7.1' in self.spec:
+            config_args.append('-no-openvg')
+        else:
+            # FIXME: those could work for other versions
+            config_args.extend([
+                '-system-libpng',
+                '-system-libjpeg',
+                '-system-zlib'
+            ])
+
         if '@:5.7.0' in self.spec:
             config_args.extend([
                 # NIS is deprecated in more recent glibc,