diff --git a/bitbake/lib/bb/parse/__init__.py b/bitbake/lib/bb/parse/__init__.py
index c973f6fdbf..97983c9880 100644
--- a/bitbake/lib/bb/parse/__init__.py
+++ b/bitbake/lib/bb/parse/__init__.py
@@ -73,9 +73,17 @@ def update_mtime(f):
 def mark_dependency(d, f):
     if f.startswith('./'):
         f = "%s/%s" % (os.getcwd(), f[2:])
-    deps = (d.getVar('__depends') or []) + [(f, cached_mtime(f))]
-    d.setVar('__depends', deps)
+    deps = (d.getVar('__depends') or [])
+    s = (f, cached_mtime_noerror(f))
+    if s not in deps:
+        deps.append(s)
+        d.setVar('__depends', deps)
 
+def check_dependency(d, f):
+    s = (f, cached_mtime_noerror(f))
+    deps = (d.getVar('__depends') or [])
+    return s in deps
+   
 def supports(fn, data):
     """Returns true if we have a handler for this file, false otherwise"""
     for h in handlers:
@@ -102,11 +110,14 @@ def init_parser(d):
 def resolve_file(fn, d):
     if not os.path.isabs(fn):
         bbpath = d.getVar("BBPATH", True)
-        newfn = bb.utils.which(bbpath, fn)
+        newfn, attempts = bb.utils.which(bbpath, fn, history=True)
+        for af in attempts:
+            mark_dependency(d, af)
         if not newfn:
             raise IOError("file %s not found in %s" % (fn, bbpath))
         fn = newfn
 
+    mark_dependency(d, fn)
     if not os.path.isfile(fn):
         raise IOError("file %s not found" % fn)
 
diff --git a/bitbake/lib/bb/parse/parse_py/BBHandler.py b/bitbake/lib/bb/parse/parse_py/BBHandler.py
index 01f22d3b24..7cba649595 100644
--- a/bitbake/lib/bb/parse/parse_py/BBHandler.py
+++ b/bitbake/lib/bb/parse/parse_py/BBHandler.py
@@ -77,7 +77,10 @@ def inherit(files, fn, lineno, d):
         if not os.path.isabs(file):
             dname = os.path.dirname(fn)
             bbpath = "%s:%s" % (dname, d.getVar("BBPATH", True))
-            abs_fn = bb.utils.which(bbpath, file)
+            abs_fn, attempts = bb.utils.which(bbpath, file, history=True)
+            for af in attempts:
+                if af != abs_fn:
+                    bb.parse.mark_dependency(d, af)
             if abs_fn:
                 file = abs_fn
 
diff --git a/bitbake/lib/bb/parse/parse_py/ConfHandler.py b/bitbake/lib/bb/parse/parse_py/ConfHandler.py
index 7b30c8acb3..f4fb2aa45c 100644
--- a/bitbake/lib/bb/parse/parse_py/ConfHandler.py
+++ b/bitbake/lib/bb/parse/parse_py/ConfHandler.py
@@ -82,9 +82,15 @@ def include(oldfn, fn, lineno, data, error_out):
     if not os.path.isabs(fn):
         dname = os.path.dirname(oldfn)
         bbpath = "%s:%s" % (dname, data.getVar("BBPATH", True))
-        abs_fn = bb.utils.which(bbpath, fn)
+        abs_fn, attempts = bb.utils.which(bbpath, fn, history=True)
+        if abs_fn and bb.parse.check_dependency(data, abs_fn):
+            bb.warn("Duplicate inclusion for %s in %s" % (abs_fn, data.getVar('FILE', True)))
+        for af in attempts:
+            bb.parse.mark_dependency(data, af)
         if abs_fn:
             fn = abs_fn
+    elif bb.parse.check_dependency(data, fn):
+        bb.warn("Duplicate inclusion for %s in %s" % (fn, data.getVar('FILE', True)))
 
     from bb.parse import handle
     try:
@@ -93,6 +99,7 @@ def include(oldfn, fn, lineno, data, error_out):
         if error_out:
             raise ParseError("Could not %(error_out)s file %(fn)s" % vars(), oldfn, lineno)
         logger.debug(2, "CONF file '%s' not found", fn)
+        bb.parse.mark_dependency(data, fn)
 
 # We have an issue where a UI might want to enforce particular settings such as
 # an empty DISTRO variable. If configuration files do something like assigning
diff --git a/bitbake/lib/bb/utils.py b/bitbake/lib/bb/utils.py
index f9ee4f1c1d..20dea64c0e 100644
--- a/bitbake/lib/bb/utils.py
+++ b/bitbake/lib/bb/utils.py
@@ -793,22 +793,28 @@ def copyfile(src, dest, newmtime = None, sstat = None):
         newmtime = sstat[stat.ST_MTIME]
     return newmtime
 
-def which(path, item, direction = 0):
+def which(path, item, direction = 0, history = False):
     """
     Locate a file in a PATH
     """
 
+    hist = []
     paths = (path or "").split(':')
     if direction != 0:
         paths.reverse()
 
     for p in paths:
         next = os.path.join(p, item)
+        hist.append(next)
         if os.path.exists(next):
             if not os.path.isabs(next):
                 next = os.path.abspath(next)
+            if history:
+                return next, hist
             return next
 
+    if history:
+        return "", hist
     return ""
 
 def to_boolean(string, default=None):