On Sun, Feb 11, 2018 at 9:06 PM, Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: > On Sun, Feb 11, 2018 at 11:53 AM, Linus Torvalds > <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: >> >> Well, it's still not a very *big* bump. With modern distros being at >> 7.3, and people testing pre-releases of gcc-8, something like gcc-4.5 >> is still pretty darn ancient. > > ... it's worth noting that our _documentation_ may claim that gcc-3.2 > is the minimum supported version, but Arnd pointed out that a few > months ago that apparently nothing older than 4.1 has actually worked > for a longish while, and gcc-4.3 was needed on several architectures. > > So the _real_ jump in required gcc version would be from 4.1 (4.3 in > many cases) to 4.5, not from our documented "3.2 minimum". > > Arnd claimed that some architectures needed even newer-than-4.3, but I > assume that's limited to things like RISC-V that simply don't have old > gcc support at all. Right. Also architecture specific features may need something more recent, and in some cases like the 'initializer for anonymous union needs extra curly braces', a trivial change would make it work, but a lot of architectures have obviously never been built with toolchains old enough to actually run into those cases. Geert is the only person I know that actively uses gcc-4.1, and he actually sent some patches that seem to get additional architectures to build on that version, when they were previously on gcc-4.3+. gcc-4.3 in turn is used by default on SLES11, which is still in support, and I've even worked with someone who used that compiler to build new kernels, since that was what happened to be installed on his shared build server. In this case, having gcc-4.3 actively refused to force him to use a new compiler would have saved us some debugging trouble. In my tests last year, I identified gcc-4.6 as a nice minimum level, IIRC gcc-4.5 was unable to build some of the newer ARM targets. Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html