c/c++ clang链接错误在Mac OSX - webkitgtk

我正在尝试使用GTK3和WebKitGTK。我成功地运行了以下代码:

#include <gtk/gtk.h>
#include <webkit2/webkit2.h>
#include <JavaScriptCore/JavaScript.h>
using namespace std;
static void destroyWindowCb(GtkWidget* widget, GtkWidget* window);
static gboolean closeWebViewCb(WebKitWebView* webView, GtkWidget* window);
int main(int argc, char* argv[])
{
// Initialize GTK+
gtk_init(&argc, &argv);
// Create an 800x600 window that will contain the browser instance
GtkWidget *main_window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
gtk_window_set_default_size(GTK_WINDOW(main_window), 800, 600);
// Create a browser instance
WebKitWebView *webView = WEBKIT_WEB_VIEW(webkit_web_view_new());
// Put the browser area into the main window
gtk_container_add(GTK_CONTAINER(main_window), GTK_WIDGET(webView));
// Set up callbacks so that if either the main window or the browser instance is
// closed, the program will exit
g_signal_connect(main_window, "destroy", G_CALLBACK(destroyWindowCb), NULL);
g_signal_connect(webView, "close", G_CALLBACK(closeWebViewCb), main_window);
// Load a web page into the browser instance
webkit_web_view_load_uri(webView, "http://www.webkitgtk.org/");
// Make sure that when the browser area becomes visible, it will get mouse
// and keyboard events
gtk_widget_grab_focus(GTK_WIDGET(webView));
// Make sure the main window and all its contents are visible
gtk_widget_show_all(main_window);
// Run the main GTK+ event loop
gtk_main();
return 0;
}

static void
destroyWindowCb(GtkWidget* widget, GtkWidget* window)
{
    gtk_main_quit();
}
static gboolean
closeWebViewCb(WebKitWebView* webView, GtkWidget* window)
{
    gtk_widget_destroy(window);
    return TRUE;
}

和下面的cmake列表:

cmake_minimum_required(VERSION 3.3)
project(HttpsMock)
# Use the package PkgConfig to detect GTK+ headers/library files
find_package(PkgConfig REQUIRED)
pkg_check_modules(GTK3 REQUIRED gtk+-3.0)
pkg_check_modules(WEBKIT REQUIRED webkitgtk-3.0)
# Setup CMake to use GTK+, tell the compiler where to look for headers
include_directories(${GTK3_INCLUDE_DIRS})
include_directories(${WEBKIT_INCLUDE_DIRS})
# and to the linker where to look for libraries
link_directories(${GTK3_LIBRARY_DIRS})
link_directories(${WEBKIT_LIBRARY_DIRS})
# Add other flags to the compiler
add_definitions(${GTK3_CFLAGS_OTHER})
add_definitions(${WEBKIT_CFLAGS_OTHER})
# Flags and source
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11 -v")
set(SOURCE_FILES main.cpp)
add_executable(HttpsMock ${SOURCE_FILES})
# Linking
target_link_libraries(HttpsMock ${GTK3_LIBRARIES})
target_link_libraries(HttpsMock ${WEBKIT_LIBRARIES})

但是一旦我尝试使用另一种方法，如:

WebKitURIRequest *request = webkit_uri_request_new("http://www.webkitgtk.org/");

程序不想再链接了。这真的很奇怪。下面是一个错误示例:

[100%] Linking CXX executable HttpsMock
Apple LLVM version 7.0.0 (clang-700.0.72)
Target: x86_64-apple-darwin14.5.0
Thread model: posix
 "/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ld" -demangle -dynamic -arch x86_64 -macosx_version_min 10.10.0 -syslibroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk -o HttpsMock -L/opt/local/lib -search_paths_first -headerpad_max_install_names CMakeFiles/HttpsMock.dir/main.cpp.o -lwebkitgtk-3.0 -lgtk-3 -lgdk-3 -lpangocairo-1.0 -lpangoft2-1.0 -lpango-1.0 -lm -lfontconfig -lfreetype -latk-1.0 -lcairo-gobject -lcairo -lgdk_pixbuf-2.0 -lsoup-2.4 -lgio-2.0 -lgobject-2.0 -ljavascriptcoregtk-3.0 -lglib-2.0 -lintl -rpath /opt/local/lib -lc++ -lSystem /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../lib/clang/7.0.0/lib/darwin/libclang_rt.osx.a
Undefined symbols for architecture x86_64:
  "_webkit_uri_request_new", referenced from:
      _main in main.cpp.o
ld: symbol(s) not found for architecture x86_64

谢谢