* libguile/modules.c (scm_module_reverse_lookup): Type-check VARIABLE.
Don't traverse the `uses' list when MODULE is #f.
* test-suite/tests/modules.test ("foundations")["module-reverse-lookup
[pre-module-obarray]", "module-reverse-lookup [wrong-type-arg]"]: New
tests.
* module/ice-9/boot-9.scm (module-name): When making MOD non-anonymous,
bind it in the `(%app modules)' name space.
* test-suite/tests/compiler.test ("psyntax")["compile in current
module", "compile in fresh module"]: New tests.
* test-suite/tests/modules.test ("foundations")["modules don't remain
anonymous"]: New test.