Simon Josefsson wrote: > Jim Meyering <[email protected]> writes: >> Eric Blake wrote: >>> On 12/03/2011 09:00 AM, Simon Josefsson wrote: >>>> What does -funit-at-a-time really do? My gcc 4.4 manual says: >>>> >>>> `-funit-at-a-time' >>>> This option is left for compatibility reasons. `-funit-at-a-time' >>>> has no effect, while `-fno-unit-at-a-time' implies >>>> `-fno-toplevel-reorder' and `-fno-section-anchors'. >>>> >>>> Enabled by default. >>> >>> That's the case for 4.4 and later. But in gcc 4.3, it was not >>> unconditionally enabled, and as I said earlier, at least coreutils ran >>> into a situation where gcc 4.3. failed to compile at -Werror because >>> -Wdisabled-optimization warned that -fno-unit-at-a-time was required, >>> which warning turned into an error. >>> >>> At this point, gcc 4.3 is slowly phasing out; most Linux distros and >>> Cygwin have moved on to newer compilers, where the problem is less >>> likely to happen. >> >> IMHO, we should treat --enable-gcc-warnings as something that must work >> well with the latest stable version of gcc (currently 4.6) and recent >> glibc headers. Trying to accommodate older versions of gcc does not seem >> worthwhile. Just tell people who use old versions of gcc not to use >> --enable-gcc-warnings, or even detect that and turn it off automatically. > > I think this is a good approach: I wouldn't want workarounds for issues > in old gcc in manywarnings.m4. Manywarnings is a maintainer tool, and > maintainers can be required to have newer tools than users, so > manywarnings could require more recent tools. However, personally I > still use gcc 4.4 on my primary development machine, so if it isn't > difficult to support it, I'd prefer that.
That is reasonable, since you'll be motivated to address any problem that is specific to your aging, er... "stable" environment ;-) Besides, if it just-works even with gcc-4.4, we'll avoid at least a few bug reports.
