depends: add a zlib build

qt5.7 changed the location of some of its symbols, creating a circular
dependency in Qt5Core. Rather than trying to fix that up, build our own zlib
rather than having it built for us.

depends/packages/packages.mk

@@ -2,7 +2,7 @@ packages:=boost openssl libevent zeromq
 native_packages := native_ccache
 
 qt_native_packages = native_protobuf
-qt_packages = qrencode protobuf
+qt_packages = qrencode protobuf zlib
 
 qt_x86_64_linux_packages:=qt expat dbus libxcb xcb_proto libXau xproto freetype fontconfig libX11 xextproto libXext xtrans
 qt_i686_linux_packages:=$(qt_x86_64_linux_packages)

depends/packages/qt.mk

@@ -4,7 +4,7 @@ $(package)_download_path=http://download.qt.io/official_releases/qt/5.7/$($(pack
 $(package)_suffix=opensource-src-$($(package)_version).tar.gz
 $(package)_file_name=qtbase-$($(package)_suffix)
 $(package)_sha256_hash=95f83e532d23b3ddbde7973f380ecae1bac13230340557276f75f2e37984e410
-$(package)_dependencies=openssl
+$(package)_dependencies=openssl zlib
 $(package)_linux_dependencies=freetype fontconfig libxcb libX11 xproto libXext
 $(package)_build_subdir=qtbase
 $(package)_qt_libs=corelib network widgets gui plugins testlib
@@ -73,7 +73,7 @@ $(package)_config_opts += -prefix $(host_prefix)
 $(package)_config_opts += -qt-libpng
 $(package)_config_opts += -qt-libjpeg
 $(package)_config_opts += -qt-pcre
-$(package)_config_opts += -qt-zlib
+$(package)_config_opts += -system-zlib
 $(package)_config_opts += -reduce-exports
 $(package)_config_opts += -static
 $(package)_config_opts += -silent

depends/packages/zlib.mk

@@ -0,0 +1,25 @@
+package=zlib
+$(package)_version=1.2.11
+$(package)_download_path=http://www.zlib.net
+$(package)_file_name=$(package)-$($(package)_version).tar.gz
+$(package)_sha256_hash=c3e5e9fdd5004dcb542feda5ee4f0ff0744628baf8ed2dd5d66f8ca1197cb1a1
+
+define $(package)_set_vars
+$(package)_build_opts= CC="$($(package)_cc)"
+$(package)_build_opts+=CFLAGS="$($(package)_cflags) $($(package)_cppflags) -fPIC"
+$(package)_build_opts+=AR="$($(package)_ar)"
+$(package)_build_opts+=RANLIB="$($(package)_ranlib)"
+endef
+
+define $(package)_config_cmds
+  ./configure --static --prefix=$(host_prefix)
+endef
+
+define $(package)_build_cmds
+  $(MAKE) $($(package)_build_opts) libz.a
+endef
+
+define $(package)_stage_cmds
+  $(MAKE) DESTDIR=$($(package)_staging_dir) install $($(package)_build_opts)
+endef
+