Cross-compiling for iPhone does not work

When trying to cross-compile click for the iPhone, I am brought this error:

In file included from paths.c:21:
In file included from /usr/include/glib-2.0/glib.h:30:
In file included from /usr/include/glib-2.0/glib/galloca.h:32:
/usr/include/glib-2.0/glib/gtypes.h:422:3: error: '_GStaticAssertCompileTimeAssertion_0' declared as an array with a negative size
  G_STATIC_ASSERT(sizeof (unsigned long long) == sizeof (guint64));
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/glib-2.0/glib/gmacros.h:217:103: note: expanded from macro 'G_STATIC_ASSERT'
#define G_STATIC_ASSERT(expr) typedef char G_PASTE (_GStaticAssertCompileTimeAssertion_, __COUNTER__)[(expr) ? 1 : -1] G_GNUC_UNUSED
                                                                                                      ^~~~~~~~~~~~~~~
1 warning and 1 error generated.

I use the following script to build click. It's quite messy, but here you go:

#!/bin/bash
rm -rf ~/built/click
PREFIX=~/toolchain/linux/iphone/bin/armv7-apple-darwin11
AR=$PREFIX-ar
AS=$PREFIX-as
CC=$PREFIX-clang
CXX=$PREFIX-clang++
LD=$PREFIX-ld
NM=$PREFIX-nm
OBJDUMP=$PREFIX-objdump
RANLIB=$PREFIX-ranlib
STRIP=$PREFIX-strip
SDK=/home/citrusui/sdks/iPhoneOS9.3.sdk
CFLAGS="-arch armv7 -arch arm64 -isysroot $SDK"
LDFLAGS="-Wl,-segalign,4000"
DESTDIR=~/built/click/
apt install autoconf bzr clang intltool libcurl4-openssl-dev libgee-0.8 libjson-glib-dev libtool xutils-dev debhelper dh-autoreconf python3-all python3-setuptools pep8 python3-pep8 pyflakes python3-sphinx valac gobject-introspection libgirepository1.0-dev libpackagekit-glib2-dev python3-coverage dh-systemd
cd ~
if [ ! -d click ]; then
bzr branch lp:click
fi
cd ~/click
./autogen.sh
./configure cross_compiling=yes --prefix=/home/citrusui/built/click --sysconfdir=/etc --with-systemdsystemunitdir=/lib/systemd/system --with-systemduserunitdir=/usr/lib/systemd/user CC="$CC" CXX="$CXX" CFLAGS="$CFLAGS" CXXFLAGS="$CFLAGS" STRIP="$STRIP" RANLIB="$RANLIB" NM=$NM AR=$AR AS=$AS LD="$LD" OBJDUMP="$OBJDUMP" LDFLAGS="$LDFLAGS" DESTDIR="$DESTDIR"
make install
cd ~/built/click

Note that ~/toolchain contains data from https://developer.angelxwind.net/Linux/ and ~/sdks/iPhoneOS9.3.sdk contains data from https://jbdevs.org/sdks/.