diff --git a/include/bal.hh b/include/bal.hh
index 5d31c3b..f42196a 100644
--- a/include/bal.hh
+++ b/include/bal.hh
@@ -26,12 +26,6 @@
 #ifndef _BAL_HH_INCLUDED
 # define _BAL_HH_INCLUDED
 
-# if defined(__has_include)
-#  define __HAS_INCLUDE(hdr) __has_include(hdr)
-# else
-#  define __HAS_INCLUDE(hdr) false
-# endif
-
 # include "bal.h"
 # include <type_traits>
 # include <functional>
@@ -41,7 +35,20 @@
 # include <vector>
 # include <atomic>
 # include <string>
-# if __HAS_INCLUDE(<bit>)
+# include <version>
+
+# if defined(__has_include)
+#  define __HAS_INCLUDE(hdr) __has_include(hdr)
+# else
+#  define __HAS_INCLUDE(hdr) false
+# endif
+
+# if defined(__cpp_lib_source_location) && __HAS_INCLUDE(<source_location>)
+#  include <source_location>
+#  define source_location std::source_location
+# endif
+
+# if defined(__cpp_lib_bit_cast) && __HAS_INCLUDE(<bit>)
 #  include <bit>
 #  define bit_cast std::bit_cast
 # else
diff --git a/include/bal/errors.h b/include/bal/errors.h
index ba9e557..a0e6f2d 100644
--- a/include/bal/errors.h
+++ b/include/bal/errors.h
@@ -161,11 +161,10 @@ bool __bal_validate(bool expr, int err, const char* func, const char* file,
 # if defined(BAL_DBGLOG)
 void __bal_dbglog(const char* func, const char* file, uint32_t line,
     const char* format, ...);
-#  if defined(__cplusplus) && __HAS_INCLUDE(<source_location>)
-#   include <source_location>
+#  if defined(__cplusplus) && defined(source_location)
 #   define _bal_dbglog(...) \
         do { \
-            std::source_location loc = std::source_location::current(); \
+            source_location loc = source_location::current(); \
             __bal_dbglog(loc.function_name(), loc.file_name(), loc.line(), __VA_ARGS__); \
         } while (false)
 #  else
diff --git a/tests/tests++.hh b/tests/tests++.hh
index 2913fc9..7cfd2f6 100644
--- a/tests/tests++.hh
+++ b/tests/tests++.hh
@@ -27,7 +27,6 @@
 # define _BAL_TESTSXX_HH_INCLUDED
 
 # include <bal.hh>
-# include <source_location>
 # include "tests_shared.h"
 
 /**
@@ -71,16 +70,34 @@ namespace bal::tests
     try { \
         initializer balinit;
 
+/** Emits an error message when an unexpected exception is caught. */
+# define _BAL_TEST_LOG_UNEXPECTED_EXCEPTION(func, what) \
+     ERROR_MSG("unexpected exception in %s: '%s'", (func), (what)); \
+     pass = false
+
+/** Emits a message when an expected exception is caught. */
+# define _BAL_TEST_LOG_EXPECTED_EXCEPTION(func, what) \
+    TEST_MSG(GREEN("expected exception in %s: '%s'"), (func), (what))
+
 /** Implements recovery in the event that an unexpected exception is caught. */
-# define _BAL_TEST_ON_EXCEPTION(ex) \
-    std::source_location loc = std::source_location::current(); \
-    ERROR_MSG("unexpected exception in %s: '%s'", loc.function_name(), ex.what()); \
-    pass = false
+# if defined(source_location)
+#  define _BAL_TEST_ON_EXCEPTION(ex) \
+     source_location loc = source_location::current(); \
+     _BAL_TEST_LOG_UNEXPECTED_EXCEPTION(loc.function_name(), ex.what())
+# else
+#  define _BAL_TEST_ON_EXCEPTION(ex) \
+    _BAL_TEST_LOG_UNEXPECTED_EXCEPTION(__func__, ex.what())
+# endif
 
 /** Handles an expected exception. */
+# if defined(source_location)
+# define _BAL_TEST_ON_EXPECTED_EXCEPTION(ex) \
+    source_location loc = source_location::current(); \
+    _BAL_TEST_LOG_EXPECTED_EXCEPTION(loc.function_name(), ex.what())
+# else
 # define _BAL_TEST_ON_EXPECTED_EXCEPTION(ex) \
-    std::source_location loc = std::source_location::current(); \
-    TEST_MSG(GREEN("expected exception in %s: '%s'"), loc.function_name(), ex.what())
+    _BAL_TEST_LOG_EXPECTED_EXCEPTION(__func__, ex.what())
+# endif
 
 # define _BAL_TEST_CONCLUDE \
     } catch (bal::exception& ex) { \