Redesign src/out scoping

We no longer enter paths from the src tree into scope map. Instead, targets
from the src tree now include their out tree directory (in essence their
"configuration"). This is then used to find a target's scope. See the
comment in class target for details.

The result of this change is that we can now again build multiple
configurations (out trees) for same project at once.

1 files changed, 2 insertions, 0 deletions

diff --git a/build2/algorithm b/build2/algorithm
index 06a5c01..19b3971 100644
--- a/build2/algorithm
+++ b/build2/algorithm
@@ -42,6 +42,7 @@ namespace build2
   target&
   search (const target_type& type,
           const dir_path& dir,
+          const dir_path& out,
           const string& name,
           const string* ext,
           scope*);
@@ -51,6 +52,7 @@ namespace build2
   template <typename T>
   T&
   search (const dir_path& dir,
+          const dir_path& out,
           const string& name,
           const string* ext,
           scope*);