On Sun, 2017-08-06 at 17:27 +0200, Adam Borowski wrote: > On Sun, Aug 06, 2017 at 09:16:48AM +0100, Ian Campbell wrote: > > What is the expected interaction with the hwcaps based library > > installed paths? (/usr/lib/i386-linux-gnu/i686/{sse2,cmov}). > > Presumably > > libraries would still be expected to use those as appropriate? > > hwcaps implies runtime detection, ie, your code runs on all CPUs, both those > with or without the extension in question. No need to say "sorry I can't > support the baseline" if you can.
I was asking about e.g. a library which only supports, say, sse2 would not run without that extension, so no baseline support is present. In that case should the library package both depend on your new metapackage _and_ also install to the sse2 hwcap directory, or are you were suggesting that if you depend on the metapackage then installing the main base library dir is ok. The practical difference would be between a library-not-found from the dynamic linker vs an undef-instruction at runtime (assuming no further runtime check is present) in the case where a user has chosen to override the metapackage somehow and is running on an unsupported platform. Ian.