Ruby » Ruby master

• gc.c (init_heap): call init_mark_stack before to allocate
  altstack. This change avoid the stack overflow at the signal
  handler on 32bit, but I don't understand reason... [Feature #7095]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@37088 b2dd03c8-39d4-4d8f-98ff-823fe69b080e