build: Suppress compiler warning if compiled with G_DISABLE_ASSERT
This not a solution. This looks like incorrect using glib assertions. https://developer.gnome.org/glib/stable/glib-Testing.html
AFAIK, this is correct:
Since 2.58, if tests are compiled with G_DISABLE_ASSERT defined, g_test_init() will print an error and exit. This is to prevent no-op tests from being executed, as g_assert() is commonly (erroneously) used in unit tests, and is a no-op when compiled with G_DISABLE_ASSERT. Ensure your tests are compiled without G_DISABLE_ASSERT defined.