2 files changed, 31 insertions, 3 deletions
diff --git a/tests/openssl/buildfile b/tests/openssl/buildfile
index 7713f14..08b0878 100644
--- a/tests/openssl/buildfile
+++ b/tests/openssl/buildfile
@@ -4,4 +4,10 @@
 
 import libs = libbutl%lib{butl}
 
+if ($cxx.features.modules && ($force_std_modules == true || $cxx.id != 'msvc'))
+{
+  import libs += libstd-modules%liba{std-modules}
+  cxx.poptions += -D__cpp_lib_modules
+}
+
 exe{driver}: {hxx cxx}{*} $libs test{testscript}
diff --git a/tests/openssl/driver.cxx b/tests/openssl/driver.cxx
index b0e37ae..092b2ba 100644
--- a/tests/openssl/driver.cxx
+++ b/tests/openssl/driver.cxx
@@ -2,14 +2,36 @@
 // copyright : Copyright (c) 2014-2017 Code Synthesis Ltd
 // license   : MIT; see accompanying LICENSE file
 
+#include <cassert>
+
+#ifndef __cpp_lib_modules
 #include <vector>
 #include <iostream>
 #include <iterator>
 #include <system_error>
+#endif
+
+// Other includes.
+
+#ifdef __cpp_modules
+#ifdef __cpp_lib_modules
+import std.core;
+import std.io;
+#endif
+import butl.path;
+import butl.utility;  // operator<<(ostream, exception)
+import butl.openssl;
+import butl.process;
+import butl.fdstream; // nullfd
 
-#include <libbutl/path.hxx>
-#include <libbutl/utility.hxx> // operator<<(ostream, exception)
-#include <libbutl/openssl.hxx>
+import butl.optional;     // @@ MOD Clang should not be necessary.
+import butl.small_vector; // @@ MOD Clang should not be necessary.
+#else
+#include <libbutl/path.mxx>
+#include <libbutl/utility.mxx>
+#include <libbutl/openssl.mxx>
+#include <libbutl/fdstream.mxx>
+#endif
 
 using namespace std;
 using namespace butl;