diff --git a/test/Unit/lit.cfg.py b/test/Unit/lit.cfg.py
index 81e8dc04acea..479ff95681e2 100644
--- a/test/Unit/lit.cfg.py
+++ b/test/Unit/lit.cfg.py
@@ -3,6 +3,7 @@
 # Configuration file for the 'lit' test runner.
 
 import os
+import platform
 import subprocess
 
 import lit.formats
@@ -55,3 +56,26 @@ if sys.platform in ['win32', 'cygwin'] and os.path.isdir(config.shlibdir):
 # Win32 may use %SYSTEMDRIVE% during file system shell operations, so propogate.
 if sys.platform == 'win32' and 'SYSTEMDRIVE' in os.environ:
     config.environment['SYSTEMDRIVE'] = os.environ['SYSTEMDRIVE']
+
+# Add the LLVM dynamic libs to the platform-specific loader search path env var:
+#
+# TODO: this is copied from `clang`'s `lit.cfg.py`; should unify..
+def find_shlibpath_var():
+    if platform.system() in ['Linux', 'FreeBSD', 'NetBSD', 'OpenBSD', 'SunOS']:
+        yield 'LD_LIBRARY_PATH'
+    elif platform.system() == 'Darwin':
+        yield 'DYLD_LIBRARY_PATH'
+    elif platform.system() == 'Windows':
+        yield 'PATH'
+    elif platform.system() == 'AIX':
+        yield 'LIBPATH'
+
+for shlibpath_var in find_shlibpath_var():
+    shlibpath = os.path.pathsep.join(
+        (config.shlibdir,
+         config.environment.get(shlibpath_var, '')))
+    config.environment[shlibpath_var] = shlibpath
+    break
+else:
+    lit_config.warning("unable to inject shared library path on '{}'"
+                       .format(platform.system()))
diff --git a/test/lit.cfg.py b/test/lit.cfg.py
index 75a38b4c5dad..856fc75c9d74 100644
--- a/test/lit.cfg.py
+++ b/test/lit.cfg.py
@@ -42,6 +42,26 @@ llvm_config.with_environment('PATH', config.llvm_tools_dir, append_path=True)
 llvm_config.with_system_environment(
     ['HOME', 'INCLUDE', 'LIB', 'TMP', 'TEMP'])
 
+# Add the LLVM dynamic libs to the platform-specific loader search path env var:
+#
+# TODO: this is copied from `clang`'s `lit.cfg.py`; should unify..
+def find_shlibpath_var():
+    if platform.system() in ['Linux', 'FreeBSD', 'NetBSD', 'OpenBSD', 'SunOS']:
+        yield 'LD_LIBRARY_PATH'
+    elif platform.system() == 'Darwin':
+        yield 'DYLD_LIBRARY_PATH'
+    elif platform.system() == 'Windows':
+        yield 'PATH'
+    elif platform.system() == 'AIX':
+        yield 'LIBPATH'
+
+for shlibpath_var in find_shlibpath_var():
+    shlibpath = config.llvm_shlib_dir
+    llvm_config.with_environment(shlibpath_var, shlibpath, append_path = True)
+    break
+else:
+    lit_config.warning("unable to inject shared library path on '{}'"
+                       .format(platform.system()))
 
 # Set up OCAMLPATH to include newly built OCaml libraries.
 top_ocaml_lib = os.path.join(config.llvm_lib_dir, 'ocaml')
@@ -318,7 +338,7 @@ def have_cxx_shared_library():
 
     try:
         readobj_cmd = subprocess.Popen(
-            [readobj_exe, '--needed-libs', readobj_exe], stdout=subprocess.PIPE)
+            [readobj_exe, '--needed-libs', readobj_exe], stdout=subprocess.PIPE, env=config.environment)
     except OSError:
         print('could not exec llvm-readobj')
         return False