7 files changed, 9 insertions, 7 deletions
diff --git a/tests/dir-iterator/driver.cxx b/tests/dir-iterator/driver.cxx
index 62f051b..d3d25b8 100644
--- a/tests/dir-iterator/driver.cxx
+++ b/tests/dir-iterator/driver.cxx
@@ -8,6 +8,7 @@
 
 #include <butl/path>
 #include <butl/path-io>
+#include <butl/utility>    // operator<<(ostream, exception)
 #include <butl/filesystem>
 
 using namespace std;
@@ -62,7 +63,7 @@ main (int argc, const char* argv[])
   }
   catch (const exception& e)
   {
-    cerr << argv[1] << ": " << e.what () << endl;
+    cerr << argv[1] << ": " << e << endl;
     return 1;
   }
 }
diff --git a/tests/link/driver.cxx b/tests/link/driver.cxx
index 3171af0..3cade44 100644
--- a/tests/link/driver.cxx
+++ b/tests/link/driver.cxx
@@ -57,7 +57,7 @@ link_dir (const dir_path& target,
   }
   catch (const system_error& e)
   {
-    //cerr << e.what () << endl;
+    //cerr << e << endl;
     return false;
   }
 
diff --git a/tests/manifest-parser/driver.cxx b/tests/manifest-parser/driver.cxx
index 1068570..76d1579 100644
--- a/tests/manifest-parser/driver.cxx
+++ b/tests/manifest-parser/driver.cxx
@@ -200,7 +200,7 @@ fail (const char* m)
   }
   catch (const manifest_parsing& e)
   {
-    //cerr << e.what () << endl;
+    //cerr << e << endl;
   }
 
   return true;
diff --git a/tests/manifest-roundtrip/driver.cxx b/tests/manifest-roundtrip/driver.cxx
index cb48e74..69fcf03 100644
--- a/tests/manifest-roundtrip/driver.cxx
+++ b/tests/manifest-roundtrip/driver.cxx
@@ -5,6 +5,7 @@
 #include <cassert>
 #include <iostream>
 
+#include <butl/utility>             // operator<<(ostream, exception)
 #include <butl/fdstream>
 #include <butl/manifest-parser>
 #include <butl/manifest-serializer>
@@ -46,7 +47,7 @@ main (int argc, char* argv[])
   }
   catch (const exception& e)
   {
-    cerr << e.what () << endl;
+    cerr << e << endl;
     return 1;
   }
 }
diff --git a/tests/manifest-serializer/driver.cxx b/tests/manifest-serializer/driver.cxx
index 310e34c..64434c9 100644
--- a/tests/manifest-serializer/driver.cxx
+++ b/tests/manifest-serializer/driver.cxx
@@ -238,7 +238,7 @@ fail (const pairs& m)
   }
   catch (const manifest_serialization& e)
   {
-    //cerr << e.what () << endl;
+    //cerr << e << endl;
   }
 
   return true;
diff --git a/tests/process/driver.cxx b/tests/process/driver.cxx
index cc806f2..1fb685c 100644
--- a/tests/process/driver.cxx
+++ b/tests/process/driver.cxx
@@ -146,7 +146,7 @@ exec (const path& p,
     if (e.child ())
       exit (1);
 
-    //cerr << args[0] << ": " << e.what () << endl;
+    //cerr << args[0] << ": " << e << endl;
     return false;
   }
 }
diff --git a/tests/target-triplet/driver.cxx b/tests/target-triplet/driver.cxx
index fe055db..24cd02f 100644
--- a/tests/target-triplet/driver.cxx
+++ b/tests/target-triplet/driver.cxx
@@ -154,7 +154,7 @@ fail (const char* s)
   }
   catch (invalid_argument& e)
   {
-    //cerr << e.what () << endl;
+    //cerr << e << endl;
   }
 
   return true;