I think it is great that =auto becomes the default. However, adding a configure option for this seems overkill. If anyone really really wishes to change the default, they can simply edit a single-line in common.opt.
Apart from that, I really cannot understand why someone would want the options none, auto or always: none is equivalent to auto-if-env but without the "if-env" escape route, and neither auto nor always allow disabling the coloring globally (which is precisely what users hating coloring are going to be asking for and they won't be happy if we tell them to recompile gcc). I think there are only two defaults that matter: auto-if-env-otherwise-never (the current one) and never-if-env-otherwise-auto. I wish we had chosen the second one earlier, but this is not such a critical feature to not change the default now. With never-if-even-otherwise-auto, an empty GCC_COLORS (or a value ="never") could disable coloring. Currently, GCC_COLORS="never" actually enables coloring (well, any value does). Cheers, Manuel.
