diff --git a/include/tao/pegtl/internal/function.hpp b/include/tao/pegtl/internal/function.hpp
index ca49d8016..390cf8905 100644
--- a/include/tao/pegtl/internal/function.hpp
+++ b/include/tao/pegtl/internal/function.hpp
@@ -17,6 +17,8 @@ namespace TAO_PEGTL_NAMESPACE::internal
    template< typename Peek, typename Func, Func Tion >
    struct function;
 
+#if defined( __GNUC__ ) || defined( __clang__ )
+
    template< bool E, typename Input, bool ( *Tion )( Input& ) noexcept( E ) >
    struct function< void, bool ( * )( Input& ) noexcept( E ), Tion >
    {
@@ -99,6 +101,174 @@ namespace TAO_PEGTL_NAMESPACE::internal
       }
    };
 
+#else
+
+   template< typename Input, bool ( *Tion )( Input& ) noexcept( true ) >
+   struct function< void, bool ( * )( Input& ) noexcept( true ), Tion >
+   {
+      using rule_t = function;
+      using subs_t = empty_list;
+
+      template< typename ParseInput >
+      [[nodiscard]] static bool match( ParseInput& in ) noexcept( true )
+      {
+         return Tion( in );
+      }
+   };
+
+   template< typename Input, bool ( *Tion )( Input& ) noexcept( false ) >
+   struct function< void, bool ( * )( Input& ) noexcept( false ), Tion >
+   {
+      using rule_t = function;
+      using subs_t = empty_list;
+
+      template< typename ParseInput >
+      [[nodiscard]] static bool match( ParseInput& in ) noexcept( false )
+      {
+         return Tion( in );
+      }
+   };
+
+   template< typename Input, typename... States, bool ( *Tion )( Input&, States... ) noexcept( true ) >
+   struct function< void, bool ( * )( Input&, States... ) noexcept( true ), Tion >
+   {
+      using rule_t = function;
+      using subs_t = empty_list;
+
+      template< apply_mode A,
+                rewind_mode M,
+                template< typename... >
+                class Action,
+                template< typename... >
+                class Control,
+                typename ParseInput >
+      [[nodiscard]] static bool match( ParseInput& in, States... st ) noexcept( true )
+      {
+         return Tion( in, st... );
+      }
+   };
+
+   template< typename Input, typename... States, bool ( *Tion )( Input&, States... ) noexcept( false ) >
+   struct function< void, bool ( * )( Input&, States... ) noexcept( false ), Tion >
+   {
+      using rule_t = function;
+      using subs_t = empty_list;
+
+      template< apply_mode A,
+                rewind_mode M,
+                template< typename... >
+                class Action,
+                template< typename... >
+                class Control,
+                typename ParseInput >
+      [[nodiscard]] static bool match( ParseInput& in, States... st ) noexcept( false )
+      {
+         return Tion( in, st... );
+      }
+   };
+
+   template< typename Peek, typename Data, bool ( *Tion )( Data ) noexcept( true ) >
+   struct function< Peek, bool ( * )( Data ) noexcept( true ), Tion >
+   {
+      using peek_t = Peek;
+      // using data_t = typename Peek::data_t;
+
+      using rule_t = function;
+      using subs_t = empty_list;
+
+      template< typename ParseInput >
+      [[nodiscard]] static bool match( ParseInput& in )
+      {
+         if( const auto t = Peek::peek( in ) ) {
+            if( Tion( t.data() ) ) {
+               in.template consume< function >( t.size() );
+               return true;
+            }
+         }
+         return false;
+      }
+   };
+
+   template< typename Peek, typename Data, bool ( *Tion )( Data ) noexcept( false ) >
+   struct function< Peek, bool ( * )( Data ) noexcept( false ), Tion >
+   {
+      using peek_t = Peek;
+      // using data_t = typename Peek::data_t;
+
+      using rule_t = function;
+      using subs_t = empty_list;
+
+      template< typename ParseInput >
+      [[nodiscard]] static bool match( ParseInput& in )
+      {
+         if( const auto t = Peek::peek( in ) ) {
+            if( Tion( t.data() ) ) {
+               in.template consume< function >( t.size() );
+               return true;
+            }
+         }
+         return false;
+      }
+   };
+
+   template< typename Peek, typename Data, typename... States, bool ( *Tion )( Data, States... ) noexcept( true ) >
+   struct function< Peek, bool ( * )( Data, States... ) noexcept( true ), Tion >
+   {
+      using peek_t = Peek;
+      // using data_t = typename Peek::data_t;
+
+      using rule_t = function;
+      using subs_t = empty_list;
+
+      template< apply_mode A,
+                rewind_mode M,
+                template< typename... >
+                class Action,
+                template< typename... >
+                class Control,
+                typename ParseInput >
+      [[nodiscard]] static bool match( ParseInput& in, States... st )
+      {
+         if( const auto t = Peek::peek( in ) ) {
+            if( Tion( t.data(), st... ) ) {
+               in.template consume< function >( t.size() );
+               return true;
+            }
+         }
+         return false;
+      }
+   };
+
+   template< typename Peek, typename Data, typename... States, bool ( *Tion )( Data, States... ) noexcept( false ) >
+   struct function< Peek, bool ( * )( Data, States... ) noexcept( false ), Tion >
+   {
+      using peek_t = Peek;
+      // using data_t = typename Peek::data_t;
+
+      using rule_t = function;
+      using subs_t = empty_list;
+
+      template< apply_mode A,
+                rewind_mode M,
+                template< typename... >
+                class Action,
+                template< typename... >
+                class Control,
+                typename ParseInput >
+      [[nodiscard]] static bool match( ParseInput& in, States... st )
+      {
+         if( const auto t = Peek::peek( in ) ) {
+            if( Tion( t.data(), st... ) ) {
+               in.template consume< function >( t.size() );
+               return true;
+            }
+         }
+         return false;
+      }
+   };
+
+#endif
+
    template< typename Peek, typename Func, Func Tion >
    inline constexpr bool enable_control< function< Peek, Func, Tion > > = false;
 
diff --git a/include/tao/pegtl/parse_error.hpp b/include/tao/pegtl/parse_error.hpp
index 9f4f6b092..fc541c169 100644
--- a/include/tao/pegtl/parse_error.hpp
+++ b/include/tao/pegtl/parse_error.hpp
@@ -9,6 +9,10 @@
 #include <type_traits>
 #include <utility>
 
+#if !defined( __cpp_exceptions )
+#error "Exception support required for tao/pegtl/parse_error.hpp"
+#endif
+
 #include "config.hpp"
 #include "parse_error_base.hpp"
 
diff --git a/include/tao/pegtl/parse_error_base.hpp b/include/tao/pegtl/parse_error_base.hpp
index 366d71749..70757b66b 100644
--- a/include/tao/pegtl/parse_error_base.hpp
+++ b/include/tao/pegtl/parse_error_base.hpp
@@ -10,6 +10,10 @@
 #include <string>
 #include <string_view>
 
+#if !defined( __cpp_exceptions )
+#error "Exception support required for tao/pegtl/parse_error_base.hpp"
+#endif
+
 #include "config.hpp"
 
 namespace TAO_PEGTL_NAMESPACE
diff --git a/src/example/pegtl/abnf2pegtl.cpp b/src/example/pegtl/abnf2pegtl.cpp
index a58bf884c..10004f7a8 100644
--- a/src/example/pegtl/abnf2pegtl.cpp
+++ b/src/example/pegtl/abnf2pegtl.cpp
@@ -30,7 +30,9 @@
 
 #include <tao/pegtl/contrib/abnf.hpp>
 #include <tao/pegtl/contrib/parse_tree.hpp>
+#if defined( __cpp_exceptions )
 #include <tao/pegtl/control/must_if.hpp>
+#endif
 
 namespace TAO_PEGTL_NAMESPACE
 {
diff --git a/src/test/pegtl/buffer_cstream_input.cpp b/src/test/pegtl/buffer_cstream_input.cpp
index 58d7fa544..ccea4001f 100644
--- a/src/test/pegtl/buffer_cstream_input.cpp
+++ b/src/test/pegtl/buffer_cstream_input.cpp
@@ -22,7 +22,7 @@ namespace TAO_PEGTL_NAMESPACE
 
    void unit_test()
    {
-      const char* const filename = "src/test/pegtl/file_data.txt";
+      const char* const filename = "src/test/pegtl/data/test_data.txt";
       {
          std::FILE* stream = internal::read_file_open( filename );
          TAO_PEGTL_TEST_ASSERT( stream != nullptr );
diff --git a/src/test/pegtl/buffer_istream_input.cpp b/src/test/pegtl/buffer_istream_input.cpp
index e0660d799..6205b963c 100644
--- a/src/test/pegtl/buffer_istream_input.cpp
+++ b/src/test/pegtl/buffer_istream_input.cpp
@@ -36,7 +36,7 @@ namespace TAO_PEGTL_NAMESPACE
          }
       }
 #endif
-      const char* filename = "src/test/pegtl/file_data.txt";
+      const char* filename = "src/test/pegtl/data/test_data.txt";
       {
          std::ifstream stream( filename );
          static_istream_input< void > in( stream );
diff --git a/src/test/pegtl/file_data.txt b/src/test/pegtl/data/test_data.txt
similarity index 100%
rename from src/test/pegtl/file_data.txt
rename to src/test/pegtl/data/test_data.txt
diff --git a/src/test/pegtl/internal_file_mapper.cpp b/src/test/pegtl/internal_file_mapper.cpp
index e107ffea1..5fa649239 100644
--- a/src/test/pegtl/internal_file_mapper.cpp
+++ b/src/test/pegtl/internal_file_mapper.cpp
@@ -37,7 +37,7 @@ namespace TAO_PEGTL_NAMESPACE
       const std::string s = "dummy content\n";
       const std::string dummy_content = s + s + s + s + s + s + s + s + s + s + s;
 
-      internal::file_mapper mapper( "src/test/pegtl/file_data.txt" );
+      internal::file_mapper mapper( "src/test/pegtl/data/test_data.txt" );
       TAO_PEGTL_TEST_ASSERT( !mapper.empty() );
       TAO_PEGTL_TEST_ASSERT( mapper.size() == 154 );
       TAO_PEGTL_TEST_ASSERT( std::string_view( mapper.data(), mapper.size() ) == dummy_content );
diff --git a/src/test/pegtl/verify_file.hpp b/src/test/pegtl/verify_file.hpp
index ce21dee14..12627b2b7 100644
--- a/src/test/pegtl/verify_file.hpp
+++ b/src/test/pegtl/verify_file.hpp
@@ -66,10 +66,10 @@ namespace TAO_PEGTL_NAMESPACE
       }
 #endif
       {
-         T in( "src/test/pegtl/file_data.txt" );
-         TAO_PEGTL_TEST_ASSERT( in.direct_source() == "src/test/pegtl/file_data.txt" );
+         T in( "src/test/pegtl/data/test_data.txt" );
+         TAO_PEGTL_TEST_ASSERT( in.direct_source() == "src/test/pegtl/data/test_data.txt" );
          TAO_PEGTL_TEST_ASSERT( parse< file_grammar >( in ) );
-         TAO_PEGTL_TEST_ASSERT( in.direct_source() == "src/test/pegtl/file_data.txt" );
+         TAO_PEGTL_TEST_ASSERT( in.direct_source() == "src/test/pegtl/data/test_data.txt" );
       }
       {
          T in( TAO_PEGTL_TEST_FILENAME );