Current code can't compile, it blows up Erlang internals

0_format_test.erl

-module(format_test).
-export([format/2]).

format(Datetime, << H, T / binary >>) when not ((H >= $a) andalso (H =< $z)) andalso
    not ((H >= $A) andalso (H =< $Z)) ->
  { Datetime, T }.

1_INFO.md

Info

I am working on Mac OS X, Snow Leopard.

Current Erlang version is:

Erlang R15B02 (erts-5.9.2) [source] [64-bit] [smp:4:4] [async-threads:0] [hipe] [kernel-poll:false] [dtrace]

The error occurs when processing the guard clause. I am aware this same guard clause could be written in different ways and the current failure could be avoided. However, I believe this is valid Erlang code and it should not blow up the compiler chain. :)

See file 2_Stacktrace for more information about the failure.

2_Stacktrace

Function: format/2
lib/elixir/test/erlang/atom_test.erl:none: internal error in v3_codegen;
crash reason: {{case_clause,
                {'EXIT',
                 {function_clause,
                  [{v3_codegen,bsm_rename_ctx,
                    [{l,
                      {call,
                       {remote,{atom,erlang},{atom,error}},
                       [{atom,badarg}],
                       [{var,ker13}]},
                      19,[],
                      [compiler_generated,7,
                       {file,"lib/elixir/test/erlang/atom_test.erl"}]},
                     ker2,cor0,true],
                    [{file,"v3_codegen.erl"},{line,323}]},
                   {v3_codegen,bsm_rename_ctx_list,4,
                    [{file,"v3_codegen.erl"},{line,388}]},
                   {v3_codegen,bsm_rename_ctx,4,
                    [{file,"v3_codegen.erl"},{line,380}]},
                   {v3_codegen,bsm_rename_ctx,4,
                    [{file,"v3_codegen.erl"},{line,345}]},
                   {v3_codegen,bsm_rename_ctx,4,
                    [{file,"v3_codegen.erl"},{line,367}]},
                   {v3_codegen,bsm_rename_ctx_list,4,
                    [{file,"v3_codegen.erl"},{line,388}]},
                   {v3_codegen,bsm_rename_ctx_list,4,
                    [{file,"v3_codegen.erl"},{line,389}]},
                   {v3_codegen,bsm_rename_ctx,4,
                    [{file,"v3_codegen.erl"},{line,361}]}]}}},
               [{compile,'-select_passes/2-anonymous-2-',2,
                 [{file,"compile.erl"},{line,473}]},
                {compile,'-internal_comp/4-anonymous-1-',2,
                 [{file,"compile.erl"},{line,273}]},
                {compile,fold_comp,3,[{file,"compile.erl"},{line,291}]},
                {compile,internal_comp,4,[{file,"compile.erl"},{line,275}]},
                {compile,'-do_compile/2-anonymous-0-',2,
                 [{file,"compile.erl"},{line,152}]}]}