doc: mention machine=default option for meson

Document the new value, as it's useful for distributions and users
who need to use a stable baseline -march

Signed-off-by: Luca Boccassi <bluca@debian.org>
Reviewed-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
Reviewed-by: Jerin Jacob <jerinj@marvell.com>

diff --git a/doc/build-sdk-meson.txt b/doc/build-sdk-meson.txt
index 912cb3a..7b80244 100644 (file)
--- a/doc/build-sdk-meson.txt
+++ b/doc/build-sdk-meson.txt
@@ -82,6 +82,8 @@ Project-specific options are passed used -Doption=value::
 
        meson -Denable_docs=true fullbuild  # build and install docs
 
+       meson -Dmachine=default  # use builder-independent baseline -march
+
 Examples of setting the same options using meson configure::
 
        meson configure -Dwerror=true
@@ -98,6 +100,9 @@ should be used to change the build settings within the directory, and when
 ``ninja`` is called to do the build itself, it will trigger the necessary
 re-scan from meson.
 
+NOTE: machine=default uses a config that works on all supported architectures
+regardless of the capabilities of the machine where the build is happening.
+
 As well as those settings taken from ``meson configure``, other options
 such as the compiler to use can be passed via environment variables. For
 example::