data/siggen: Add vardepvalue mechanism to allow the variable dependency code to be forced to specific values

We have a problem if we want to inject specific information into the variable
dependency code. There are cases for example where we want a dependency
on the value of X but it doesn't matter how X was constructed or what
dependencies it might have had, we only care about the absolute value.
With the current code, its near enough impossible to do this.

This patch adds such a mechanism so the user can trigger this with code like:

baselib[vardepvalue] = "${baselib}"

It also refactors some of the code so we do variable lookups once
instead of doing this in two different functions.

[YOCTO #1583]

(Bitbake rev: 6c879b44ccf42dc73fe4467076e114700d7ba81b)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 1 insertions, 2 deletions

diff --git a/bitbake/lib/bb/siggen.py b/bitbake/lib/bb/siggen.py
index 9231291b43..758074287d 100644
--- a/bitbake/lib/bb/siggen.py
+++ b/bitbake/lib/bb/siggen.py
@@ -72,11 +72,10 @@ class SignatureGeneratorBasic(SignatureGenerator):
 
     def _build_data(self, fn, d):
 
-        tasklist, gendeps = bb.data.generate_dependencies(d)
+        tasklist, gendeps, lookupcache = bb.data.generate_dependencies(d)
 
         taskdeps = {}
         basehash = {}
-        lookupcache = {}
 
         for task in tasklist:
             data = d.getVar(task, False)