iOS: Link to the platform plugin and iosmain plugin and define main

Ideally we'd only have to do QTPLUGIN += ios, but this doesn't work as
we need to link with the force_load linker option. Even trying to build
on QTPLUGIN and then replace the -l line with what we need will fail, as
the prl logic in qmake which runs after all the prf files does not know
about the force_load option and will then fail to resolve dependencies
from the prl file.

Since we load the platform plugin using -force_load, there's no need to
generate a cpp file that does the plugin import.

The main wrapper is not a real Qt plugin, and doesn't have an import
function that we can call, so we link it manually instead of relying
on QTPLUGIN.

Change-Id: I0381a3c9ed7f8d41a4121e1fc0b7c0e210a8b832
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@digia.com>

1 files changed, 22 insertions, 0 deletions

diff --git a/mkspecs/features/ios/default_post.prf b/mkspecs/features/ios/default_post.prf
index 3e9d12be3b..6c6d8d89ce 100644
--- a/mkspecs/features/ios/default_post.prf
+++ b/mkspecs/features/ios/default_post.prf
@@ -10,4 +10,26 @@ isEmpty(MAKEFILE_GENERATOR) {
         MAKEFILE_GENERATOR = UNIX
 }
 
+gui_app {
+    # We have to do the link and dependency resolution for the platform plugin
+    # manually, since QTPLUGIN and the prl lookup logic does not support
+    # the -force_load link style. The -force_load option ensures that all
+    # symbols from the static library are included, not just the ones the
+    # linker have seen a use for so far. We need this because we load the platform
+    # plugin from the platform plugin itself, using Q_IMPORT_PLUGIN.
+    lib_path_and_base = $$[QT_INSTALL_PLUGINS/get]/platforms/libqios$$qtPlatformTargetSuffix()
+    LIBS += "-force_load $${lib_path_and_base}.$${QMAKE_EXTENSION_STATICLIB}"
+    LIBS += $$fromfile($${lib_path_and_base}.prl, QMAKE_PRL_LIBS)
+
+    # Which means we don't want the auto-generated import for the platform plugin
+    CONFIG -= import_qpa_plugin
+
+    # We link the iosmain library manually as well, since it's not really a plugin
+    lib_name = qiosmain
+    lib_path_and_base = $$[QT_INSTALL_PLUGINS/get]/platforms/lib$${lib_name}$$qtPlatformTargetSuffix()
+    LIBS += -L$$[QT_INSTALL_PLUGINS/get]/platforms -l$${lib_name}$$qtPlatformTargetSuffix()
+    LIBS += $$fromfile($${lib_path_and_base}.prl, QMAKE_PRL_LIBS)
+    DEFINES += main=qt_main
+}
+
 load(default_post)