yocto-compat-layer: test signature differences when setting MACHINE

Selecting a machine is only allowed to affect the signature of tasks
that are specific to that machine. In other words, when MACHINE=A and
MACHINE=B share a recipe foo and the output of foo, then both machine
configurations must build foo in exactly the same way. Otherwise it is
not possible to use both machines in the same distribution.

This criteria can only be tested by testing different machines in combination,
i.e. one main layer, potentially several additional BSP layers and an explicit
choice of machines:
yocto-compat-layer --additional-layers .../meta-intel --machines intel-corei7-64 imx6slevk -- .../meta-freescale

To simplify the analysis and limit the amount of output, mismatches
are sorted by task order such that tasks that run first are also
reported first. Following tasks for the same recipe and set of
machines then get pruned, because they are likely to be different
because of the underlying task (same approach as in
test_signatures). The difference here is that we get information about
all machines. The task order in the base configuration serves as
heuristic for sorting that merged list.

The test has already found issues in go-cross (depended on
tune-specific libgcc) and gdb-cross (had a tune-specific path
unnecessarily), so it is also useful to uncover issues that are not
caused by the BSP layer itself.

Signed-off-by: Patrick Ohly <patrick.ohly@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/scripts/yocto-compat-layer.py b/scripts/yocto-compat-layer.py
index daf3a6a32a..0d5700b538 100755
--- a/scripts/yocto-compat-layer.py
+++ b/scripts/yocto-compat-layer.py
@@ -49,6 +49,8 @@ def main():
             help='File to output log (optional)', action='store')
     parser.add_argument('--dependency', nargs="+",
             help='Layers to process for dependencies', action='store')
+    parser.add_argument('--machines', nargs="+",
+            help='List of MACHINEs to be used during testing', action='store')
     parser.add_argument('--additional-layers', nargs="+",
             help='List of additional layers to add during testing', action='store')
     parser.add_argument('-n', '--no-auto', help='Disable auto layer discovery',
@@ -162,6 +164,7 @@ def main():
         logger.info('Getting initial signatures ...')
         td['builddir'] = builddir
         td['sigs'], td['tunetasks'] = get_signatures(td['builddir'])
+        td['machines'] = args.machines
 
         if not add_layer(bblayersconf, layer, dep_layers, logger):
             logger.info('Skipping %s ???.' % layer['name'])