Package: dpkg-dev Version: 1.18.10 Severity: wishlist Dear Maintainer,
Many software packages (e.g. see #833846) like to set optimisation flags based on autodetecting CPU features of the build machine. Of course this is not suitable for binary distributors in general, and for Debian package maintainers should instead hard-code optimisation flags based on DEB_HOST_ARCH. However as far as I can tell, there is no central documentation resource that describes the optimisation flags suitable for each Debian architecture. Because of this, in practise package maintainers will just disable all build-time CPU detection to avoid generating illegal instructions. I have done this myself in the past, and this is what I suggest in #833846. But it's a shame to disable *all* optimisations. dpkg-buildflags would be a good place to put these flags. Maintainers can do what they were doing before (disable build-time CPU autodetection) but still get a somewhat-optimised build - in fact, the most optimised that it can validly be for a Debian binary package. It would also act as a good central location to document which instructions each Debian architecture actually supports, and including how this might change over time - e.g. how i386 was bumped up to requiring i686 this May. X -- System Information: Debian Release: stretch/sid APT prefers testing APT policy: (990, 'testing'), (500, 'stable'), (300, 'unstable'), (200, 'experimental') Architecture: amd64 (x86_64) Foreign Architectures: i386 Kernel: Linux 4.6.0-1-amd64 (SMP w/4 CPU cores) Locale: LANG=en_GB.utf8, LC_CTYPE=en_GB.utf8 (charmap=UTF-8) Shell: /bin/sh linked to /bin/dash Init: systemd (via /run/systemd/system) Versions of packages dpkg-dev depends on: ii base-files 9.6 ii binutils 2.26.1-1 ii bzip2 1.0.6-8 ii libdpkg-perl 1.18.10 ii make 4.1-9 ii patch 2.7.5-1 ii tar 1.29b-1 ii xz-utils 5.1.1alpha+20120614-2.1 Versions of packages dpkg-dev recommends: ii build-essential 12.2 ii fakeroot 1.21-1 ii gcc [c-compiler] 4:5.3.1-3 ii gcc-4.8 [c-compiler] 4.8.5-4 ii gcc-4.9 [c-compiler] 4.9.3-14 ii gcc-5 [c-compiler] 5.4.0-6 ii gnupg 1.4.20-6 ii gnupg2 2.1.11-7 ii gpgv 1.4.20-6 ii libalgorithm-merge-perl 0.08-3 Versions of packages dpkg-dev suggests: ii debian-keyring 2016.07.02 -- no debconf information
