Warn that it was ignored in crossbuild
MODIFY
mrbgems/mruby-bin-config/mrbgem.rake
mrbgems/mruby-bin-config/mrbgem.rake
-unless MRuby::Build.current.kind_of?(MRuby::CrossBuild)
+if MRuby::Build.current.kind_of?(MRuby::CrossBuild)
+ gemname = File.basename File.dirname __FILE__
+ buildname = MRuby::Build.current.name
+ $stderr.puts "WARN #{gemname} - This mrbgem is ignored within #{buildname}"
+else
MRuby::Gem::Specification.new('mruby-bin-config') do |spec|
name = 'mruby-config'
spec.license = 'MIT'

Warn that it was ignored in crossbuild