Bug#954917: Do not rely on autodetection for CPU optimisations (SSE, SSE3, AVX)

[Laurent Bigonville]

Source: gdal
Version: 3.0.4+dfsg-1
Severity: important

Hello,

I see that the configure is autodetecting at buildtime whether several
CPU optimisations (SSE, SSE3, AVX) should be enabled or not.

I feel this is not OK as building the package on different hardware
would result in different binaries being generated.

AFAICS, the code is detecting at runtime if the CPU is supporting these
features, so I think that it's fine to force enable these 3 on i386 and
amd64 and not rely on autodetection in the configure (and force disable
them on the other architectures).

On x32 port, the package FTBFS due to an issue related to this.

Kind regards,

Laurent Bigonville

-- System Information:
Debian Release: bullseye/sid
  APT prefers unstable-debug
  APT policy: (500, 'unstable-debug'), (500, 'unstable'), (1, 'experimental-debug'), (1, 'experimental')
Architecture: amd64 (x86_64)

Kernel: Linux 5.4.0-4-amd64 (SMP w/8 CPU cores)
Kernel taint flags: TAINT_WARN
Locale: LANG=fr_BE.UTF-8, LC_CTYPE=fr_BE.UTF-8 (charmap=UTF-8), LANGUAGE=fr_BE:fr (charmap=UTF-8)
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: SELinux: enabled - Mode: Permissive - Policy name: refpolicy