> > I believe [--set_all_file_dates] is entirely unnecessary > > if SOURCE_DATE_EPOCH sets the default, there must be some option to set > non-default values, especially the value which is default without > SOURCE_DATE_EPOCH.
Consider the state space: If someone does not set SOURCE_DATE_EPOCH, they are going to get an unreproducible regardless. Therefore, whichever set_all_file_dates option they choose is entirely meaningless and thus xorriso can simply inherit {a,c,m}time just as before. If someone does set SOURCE_DATE_EPOCH, they want a reproducible image by definition. Thus, inheriting {a,c}time from the filesystem makes no sense as their image will then not be reproducible and setting {a,c,m}time to a specific date is not necessary as that can be trivially done pre-build. Therefore folding it all into inheriting {a,c}time from mtime iff S_D_E is the logical conclusion, from the angles of complicating xorriso itself and complicating the end-user UI for someone who wants a reproducible ISO. Putting it another way, the "semi-reproducible" scenario seems so unlikely we can entirely discount it and thus there is need to for people who "just" want a reproducible ISO to tediously scour the documentation to discover they need to set --set_all_file_dates. > I decided to let SOURCE_DATE_EPOCH only set the defaults of existing > and new options, in order to protect ISO producers like grub-mkrescue from > negative effects by overriding their program options. They won't be run with SOURCE_DATE_EPOCH exported. > Not to forget that it offers those users a workaround, who do not agree > with the final decision about the question posed here, but want to use > SOURCE_DATE_EPOCH nevertheless. I just don't see this usecase of being "partly" reproducible being remotely useful to anyone, ever. I'm probably misunderstanding something, however. Regards, -- ,''`. : :' : Chris Lamb `. `'` la...@debian.org / chris-lamb.co.uk `-