On Tue, Apr 17, 2018 at 10:27 AM, Lars Schneider <larsxschneider@xxxxxxxxx> wrote: > >> On 16 Apr 2018, at 19:45, Jacob Keller <jacob.keller@xxxxxxxxx> wrote: >> >> On Mon, Apr 16, 2018 at 10:43 AM, Jacob Keller <jacob.keller@xxxxxxxxx> wrote: >>> On Mon, Apr 16, 2018 at 9:07 AM, Lars Schneider >>> <larsxschneider@xxxxxxxxx> wrote: >>>> What if Git kept a LRU list that contains file path, content hash, and >>>> mtime of any file that is removed or modified during a checkout. If a >>>> file is checked out later with the exact same path and content hash, >>>> then Git could set the mtime to the previous value. This way the >>>> compiler would not think that the content has been changed since the >>>> last rebuild. >>> >>> That would only work until they actuall *did* a build on the second >>> branch, and upon changing back, how would this detect that it needs to >>> update mtime again? I don't think this solution really works. >>> Ultimately, the problem is that the build tool relies on the mtime to >>> determine what to rebuild. I think this would cause worse problems >>> because we *wouldn't* rebuild in the case. How is git supposed to know >>> that we rebuilt when switching branches or not? >>> >>> Thanks, >>> Jake >> >> I think a better solution for your problem would be to extend the >> build system you're using to avoid rebuilding when the contents >> haven't changed since last build (possibly by using hashes?). At the >> very least, I would not want this to be default, as it could possibly >> result in *no* build when there should be one, which is far more >> confusing to debug. > > I am 100% with you that this is a build system issue. But changing > the build system for many teams in a large organization is really > hard. That's why I wondered if Git could help with a shortcut. > Looks like there is no shortcut (see my other reply in this thread). > > Thanks > Lars Right. I think that solutions involving hooks or scripts which "fix" the mtimes are the best bet for this problem then, given that building it into git would cause problems for other users. (And personally I would always ere on the side of causing rebuilds unless we're 100% sure) Thanks, Jake
