From 2be3f829e9913a0ac42b6abd6c698838ba029ad0 Mon Sep 17 00:00:00 2001
From: David James <davidjames@google.com>
Date: Wed, 21 Jul 2010 14:17:05 -0700
Subject: [PATCH] Fix infinite recursion in PrebuiltsReady when graph is
 cyclic.

Our package graph is cyclic, so parallel_emerge needs to handle cycles
correctly in all cases. PrebuiltsReady should only need to check each package
once, so we should set cache[pkg] to True if we found the package in the cache.

TEST=Ran build_packages --fast
BUG=none

Review URL: http://codereview.chromium.org/3047009
---
 parallel_emerge | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/parallel_emerge b/parallel_emerge
index 5b09ec6e42..971e6a30b3 100755
--- a/parallel_emerge
+++ b/parallel_emerge
@@ -819,11 +819,12 @@ class DepGraphGenerator(object):
         if pkg not in pkg_db:
           cache[pkg] = False
         else:
+          cache[pkg] = True
           for dep in deps_map[pkg]["needs"]:
             if not PrebuiltsReady(dep, pkg_db, cache):
               cache[pkg] = False
               break
-        return cache.setdefault(pkg, True)
+        return cache[pkg]
 
       def LastModifiedWithDeps(pkg, pkg_db, cache):
         """Calculate the last modified time of a package and its dependencies.