diff --git a/packages/build.py b/packages/build.py
index b01fbcb..523e05a 100644
--- a/packages/build.py
+++ b/packages/build.py
@@ -484,6 +484,8 @@ def build_package(
             extra_packages=['base-devel'] + CROSSDIRECT_PKGS,
             clean_chroot=clean_chroot,
         )
+    if not package.mode:
+        logging.warning('Package {package.path} has no _mode set, assuming "host"')
     cross = foreign_arch and package.mode == 'cross' and enable_crosscompile
 
     if cross:
diff --git a/packages/pkgbuild.py b/packages/pkgbuild.py
index 227449a..f36b399 100644
--- a/packages/pkgbuild.py
+++ b/packages/pkgbuild.py
@@ -294,7 +294,11 @@ def parse_pkgbuild(
     if mode not in ['host', 'cross']:
         err = 'an invalid' if mode is not None else 'no'
         err_end = f": {repr(mode)}" if mode is not None else "."
-        raise Exception(f'{relative_pkg_dir}/PKGBUILD has {err} mode configured{err_end}')
+        msg = f'{relative_pkg_dir}/PKGBUILD has {err} mode configured{err_end}'
+        if mode is None:
+            logging.warning(msg)
+        else:
+            raise Exception(msg)
 
     base_package = Pkgbase(relative_pkg_dir, sources_refreshed=sources_refreshed, srcinfo_cache=srcinfo_cache)
     base_package.mode = mode