diff --git a/Lib/inspect.py b/Lib/inspect.py
index 2e4d987..bf7f006 100644
--- a/Lib/inspect.py
+++ b/Lib/inspect.py
@@ -353,7 +353,13 @@
         if 'b' in mode and string.lower(filename[-len(suffix):]) == suffix:
             # Looks like a binary file.  We want to only return a text file.
             return None
-    if os.path.exists(filename) or hasattr(getmodule(object), '__loader__'):
+    if os.path.exists(filename):
+        return filename
+    # Ugly but necessary - '<stdin>' and '<string>' mean that getmodule()
+    # would infinitely recurse, because they're not real files nor loadable
+    # Note that this means that writing a PEP 302 loader that uses '<'
+    # at the start of a filename is now not a good idea.  :(
+    if filename[:1]!='<' and hasattr(getmodule(object), '__loader__'):
         return filename
 
 def getabsfile(object):
@@ -406,7 +412,11 @@
     in the file and the line number indexes a line in that list.  An IOError
     is raised if the source code cannot be retrieved."""
     file = getsourcefile(object) or getfile(object)
-    lines = linecache.getlines(file, getmodule(object).__dict__)
+    module = getmodule(object)
+    if module:
+        lines = linecache.getlines(file, module.__dict__)
+    else:
+        lines = linecache.getlines(file)
     if not lines:
         raise IOError('could not get source code')