sdcc --help says that --int-long-reent and --float-reent are code generation options. However IMO they only make sense for ports that generate non-reentrant code by default. Therefore IMO, these options should be listed as port-specific.
The situation is similar with --xram-movc, which AFAIK, applies to the mcs51 only.
Philipp
Duplicate to bug #1830.