What I expected to happen was that red wool would not be craft-able since there are no roses, therefore no rose red dye.
What actually happened was it was included in the crafting menu, but can't be crafted because we can't obtain rose red dye.
Steps to Reproduce:
1. Open up the crafting menu in either your inventory or a crafting table.
2. Select the decorations section.
3. Search for the red wool block and select it when you find it.
4. Notice that rose red dye is included in the recipe, but is not obtainable.
Red rose dye is obtainable by smelting red mushrooms on your furnace, so this is not a bug. You can craft the red wool once you have it.