diff --git a/lldb/packages/Python/lldbsuite/__init__.py b/lldb/packages/Python/lldbsuite/__init__.py
--- a/lldb/packages/Python/lldbsuite/__init__.py
+++ b/lldb/packages/Python/lldbsuite/__init__.py
@@ -6,7 +6,8 @@
 
 
 def find_lldb_root():
-    lldb_root = os.path.dirname(inspect.getfile(inspect.currentframe()))
+    lldb_root = os.path.realpath(
+        os.path.dirname(inspect.getfile(inspect.currentframe())))
     while True:
         parent = os.path.dirname(lldb_root)
         if parent == lldb_root: # dirname('/') == '/'
diff --git a/lldb/packages/Python/lldbsuite/test/lldbtest.py b/lldb/packages/Python/lldbsuite/test/lldbtest.py
--- a/lldb/packages/Python/lldbsuite/test/lldbtest.py
+++ b/lldb/packages/Python/lldbsuite/test/lldbtest.py
@@ -496,8 +496,12 @@
             mydir = TestBase.compute_mydir(__file__)
         '''
         # /abs/path/to/packages/group/subdir/mytest.py -> group/subdir
-        rel_prefix = test_file[len(os.environ["LLDB_TEST_SRC"]) + 1:]
-        return os.path.dirname(rel_prefix)
+        lldb_test_src = os.environ["LLDB_TEST_SRC"]
+        if not test_file.startswith(lldb_test_src):
+          raise Exception(
+              "Test file '%s' must reside within LLDB_TEST_SRC "
+              "(which is '%s')." % (test_file, lldb_test_src))
+        return os.path.dirname(os.path.relpath(test_file, start=lldb_test_src))
 
     def TraceOn(self):
         """Returns True if we are in trace mode (tracing detailed test execution)."""
diff --git a/lldb/test/API/use_lldb_suite.py b/lldb/test/API/use_lldb_suite.py
--- a/lldb/test/API/use_lldb_suite.py
+++ b/lldb/test/API/use_lldb_suite.py
@@ -4,9 +4,8 @@
 
 
 def find_lldb_root():
-    lldb_root = os.path.dirname(
-        os.path.abspath(inspect.getfile(inspect.currentframe()))
-    )
+    lldb_root = os.path.realpath(
+        os.path.dirname(inspect.getfile(inspect.currentframe())))
     while True:
         parent = os.path.dirname(lldb_root)
         if parent == lldb_root: # dirname('/') == '/'