Added example for cross-compiling for Renesas RX630

examples/targets/build_config_RX630.rb

+MRuby::Build.new do |conf|
+
+  # Gets set by the VS command prompts.
+  if ENV['VisualStudioVersion'] || ENV['VSINSTALLDIR']
+    toolchain :visualcpp
+  else
+    toolchain :gcc
+  end
+
+  enable_debug
+
+  # include the default GEMs
+  conf.gembox 'default'
+
+end
+
+# Cross Compiling configuration for RX630
+# http://gadget.renesas.com/
+#
+# Requires gnurx_v14.03
+MRuby::CrossBuild.new("RX630") do |conf|
+  toolchain :gcc
+
+  # Linux
+  BIN_PATH = "/usr/share/gnurx_v14.03_elf-1/bin"
+
+  conf.cc do |cc|
+    cc.command = "#{BIN_PATH}/rx-elf-gcc"
+    cc.flags = "-Wall -g -O2 -flto -mcpu=rx600 -m64bit-doubles"
+    cc.compile_options = "%{flags} -o %{outfile} -c %{infile}"
+
+    #configuration for low memory environment
+    cc.defines << %w(MRB_USE_FLOAT)
+    cc.defines << %w(MRB_HEAP_PAGE_SIZE=64)
+    cc.defines << %w(MRB_USE_IV_SEGLIST)
+    cc.defines << %w(KHASH_DEFAULT_SIZE=8)
+    cc.defines << %w(MRB_STR_BUF_MIN_SIZE=20)
+    cc.defines << %w(MRB_GC_STRESS)
+    cc.defines << %w(MRB_DISABLE_STDIO) #if you dont need stdio.
+    #cc.defines << %w(POOL_PAGE_SIZE=1000) #effective only for use with mruby-eval
+  end
+
+  conf.cxx do |cxx|
+    cxx.command = conf.cc.command.dup
+    cxx.include_paths = conf.cc.include_paths.dup
+    cxx.flags = conf.cc.flags.dup
+    cxx.defines = conf.cc.defines.dup
+    cxx.compile_options = conf.cc.compile_options.dup
+  end
+
+  conf.linker do |linker|
+    linker.command="#{BIN_PATH}/rx-elf-ld"
+  end
+
+  conf.archiver do |archiver|
+    archiver.command = "#{BIN_PATH}/rx-elf-ar"
+    archiver.archive_options = 'rcs %{outfile} %{objs}'
+  end
+
+  #no executables
+  conf.bins = []
+
+  #do not build executable test
+  conf.build_mrbtest_lib_only
+
+  #disable C++ exception
+  conf.disable_cxx_exception
+
+  #gems from core
+  conf.gem :core => "mruby-sprintf"
+  conf.gem :core => "mruby-print"
+  conf.gem :core => "mruby-math"
+  conf.gem :core => "mruby-enum-ext"
+  conf.gem :core => "mruby-numeric-ext"
+
+  #light-weight regular expression
+  #conf.gem :github => "masamitsu-murase/mruby-hs-regexp", :branch => "master"
+
+  #Arduino API
+  #conf.gem :github =>"kyab/mruby-arduino", :branch => "master"
+
+end