Remove -Werror from default CFLAGS

The set of warnings emitted are dependent on compiler version,
optimization level, CPU architecture, dependency versions, etc. It's not
tractable for a code base to be warning free under all circumstances,
and it's widely agreed that -Werror should not be enabled by default.

Given that it's trivial for developers to enable -Werror for autotools
by settings CFLAGS=-Werror and for meson with -Dwerror=true we should
not enable -Werror by default and require builders to disable it.


Reviewed-by: Eric Anholt <>
12 jobs for no-werror in 1 minute and 58 seconds (queued for 1 second)