Add zlib as a build-dep of Tcl/Tk

This allows the shared libraries to statically link libz.a. I think we
were previously picking up the zlib headers from the OS, and we were
previously building static libraries so that was okay - they got linked
into CPython itself which had the zlib symbols. But now that we're
building shared libraries, they're picking up a dependency on libz.so.1,
presumably because we don't have a static zlib installed from the OS.

Author: geofft

cpython-unix/Makefile

@@ -192,7 +192,13 @@ $(OUTDIR)/patchelf-$(PATCHELF_VERSION)-$(PACKAGE_SUFFIX).tar: $(PYTHON_DEP_DEPEN
 $(OUTDIR)/sqlite-$(SQLITE_VERSION)-$(PACKAGE_SUFFIX).tar: $(PYTHON_DEP_DEPENDS) $(HERE)/build-sqlite.sh
 	$(RUN_BUILD) --docker-image $(DOCKER_IMAGE_BUILD) sqlite
 
-$(OUTDIR)/tcl-$(TCL_VERSION)-$(PACKAGE_SUFFIX).tar: $(PYTHON_DEP_DEPENDS) $(HERE)/build-tcl.sh
+TCL_DEPENDS = \
+    $(PYTHON_DEP_DEPENDS) \
+    $(HERE)/build-tcl.sh \
+    $(OUTDIR)/zlib-$(ZLIB_VERSION)-$(PACKAGE_SUFFIX).tar \
+    $(NULL)
+
+$(OUTDIR)/tcl-$(TCL_VERSION)-$(PACKAGE_SUFFIX).tar: $(TCL_DEPENDS)
 	$(RUN_BUILD) --docker-image $(DOCKER_IMAGE_BUILD) tcl
 
 TK_DEPENDS = \

cpython-unix/build-tcl.sh

@@ -49,8 +49,9 @@ rm -rf pkgs/sqlite* pkgs/tdbc*
 pushd unix
 
 CFLAGS="${EXTRA_TARGET_CFLAGS} -fPIC -I${TOOLS_PATH}/deps/include"
+LDFLAGS="${EXTRA_TARGET_CFLAGS} -L${TOOLS_PATH}/deps/lib"
 
-CFLAGS="${CFLAGS}" CPPFLAGS="${CFLAGS}" LDFLAGS="${EXTRA_TARGET_LDFLAGS}" ./configure \
+CFLAGS="${CFLAGS}" CPPFLAGS="${CFLAGS}" LDFLAGS="${LDFLAGS}" ./configure \
     --build=${BUILD_TRIPLE} \
     --host=${TARGET_TRIPLE} \
     --prefix=/tools/deps \

cpython-unix/build.py

@@ -1121,6 +1121,9 @@ def main():
             "zstd",
         ):
             tools_path = "host" if action in ("m4", "patchelf") else "deps"
+            extra_archives = {
+                "tcl": {"zlib"},
+            }.get(action)
 
             simple_build(
                 settings,
@@ -1131,6 +1134,7 @@ def main():
                 target_triple=target_triple,
                 build_options=build_options,
                 dest_archive=dest_archive,
+                extra_archives=extra_archives,
                 tools_path=tools_path,
             )
 
@@ -1195,7 +1199,7 @@ def main():
             )
 
         elif action == "tk":
-            extra_archives = {"tcl"}
+            extra_archives = {"tcl", "zlib"}
             if not host_platform.startswith("macos_"):
                 extra_archives |= {
                     "libX11",