On Thu, Apr 20, 2017 at 3:15 AM, Arnd Bergmann arnd@arndb.de wrote:
On Sun, Apr 16, 2017 at 9:52 PM, Kees Cook keescook@chromium.org wrote:
The original gcc-4.3 release was in early 2008. If we decide to still support that, we probably want the first 10 quirks in this series, while gcc-4.6 (released in 2011) requires none of them.
I'd be in support of raising the minimum to gcc 4.6. (I'd actually prefer 4.7, just to avoid some 4.6 packaging issues, and for better gcc plugin support.)
I'm curious what gcc 4.6 binaries are common in the wild besides old-stable Debian (unsupported in maybe a year from now?) and 12.04 Ubuntu (going fully unsupported in 2 weeks). It looks like 4.6 was used only in Fedora 15 and 16 (both EOL).
I think we are better off defining two versions: One that we know a lot of people care about, and we actively try to make that work well in all configurations (e.g. 4.6, 4.7 or 4.8), fixing all warnings we run into, and an older version that we try not to break intentionally (e.g. 3.4, 4.1 or 4.3) but that we only fix when someone actually runs into a problem they can't work around by upgrading to a more modern compiler.
For "working well everywhere" I feel like 4.8 is the better of those three (I'd prefer 4.9). I think we should avoid 4.6 -- it seems not widely used.
For an old compiler... yikes. 3.4 sounds insane to me. :)
-Kees