[COMMITTERS] pgsql: Guard against null arguments in binary_upgrade_create_empty_exte

Guard against null arguments in binary_upgrade_create_empty_extension(). The CHECK_IS_BINARY_UPGRADE macro is not sufficient security protection if we're going to dereference pass-by-reference arguments before it. But in any case we really need to explicitly check PG_ARGISNULL for all the argumen

[COMMITTERS] pgsql: Guard against null arguments in binary_upgrade_create_empty_exte

Guard against null arguments in binary_upgrade_create_empty_extension(). The CHECK_IS_BINARY_UPGRADE macro is not sufficient security protection if we're going to dereference pass-by-reference arguments before it. But in any case we really need to explicitly check PG_ARGISNULL for all the argumen