Merge branch 'atomic-older-cplusplus' into 'main'

gatomic: fix the atomic compare_and_exchange macros on older C++ standard versions

See merge request GNOME/glib!2864

gio/tests/meson.build

@@ -27,6 +27,8 @@ if cc.has_header('pty.h')
   endif
 endif
 
+test_cpp_args = test_c_args
+
 if host_machine.system() == 'windows'
   common_gio_tests_deps += [iphlpapi_dep, winsock2, cc.find_library ('secur32')]
 endif
@@ -130,8 +132,19 @@ if have_cxx
   gio_tests += {
     'cxx' : {
       'source' : ['cxx.cpp'],
+      'suite': ['C++'],
     },
   }
+
+  foreach std, arg: cxx_standards
+    gio_tests += {
+      'cxx-@0@'.format(std) : {
+        'source' : ['cxx.cpp'],
+        'suite' : ['cpp'],
+        'cpp_args' : [arg],
+      },
+    }
+  endforeach
 endif
 
 test_extra_programs = {
@@ -882,6 +895,7 @@ foreach test_name, extra_args : gio_tests
 
   exe = executable(test_name, [source, extra_sources],
     c_args : test_c_args + extra_args.get('c_args', []),
+    cpp_args : test_cpp_args + extra_args.get('cpp_args', []),
     dependencies : common_gio_tests_deps + extra_args.get('dependencies', []),
     install_rpath : extra_args.get('install_rpath', ''),
     install_dir: installed_tests_execdir,

glib/gatomic.h

@@ -170,7 +170,7 @@ G_END_DECLS
     (void) (0 ? *(atomic) ^ *(atomic) : 1);                                  \
     __atomic_fetch_sub ((atomic), 1, __ATOMIC_SEQ_CST) == 1;                 \
   }))
-#if defined(glib_typeof) && defined(__cplusplus) && __cplusplus >= 201103L
+#if defined(glib_typeof) && defined(__cplusplus)
 /* See comments below about equivalent g_atomic_pointer_compare_and_exchange()
  * shenanigans for type-safety when compiling in C++ mode. */
 #define g_atomic_int_compare_and_exchange(atomic, oldval, newval) \
@@ -180,7 +180,7 @@ G_END_DECLS
     (void) (0 ? *(atomic) ^ (newval) ^ (oldval) : 1);                        \
     __atomic_compare_exchange_n ((atomic), &gaicae_oldval, (newval), FALSE, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST) ? TRUE : FALSE; \
   }))
-#else /* if !(defined(glib_typeof) && defined(__cplusplus) && __cplusplus >= 201103L) */
+#else /* if !(defined(glib_typeof) && defined(__cplusplus)) */
 #define g_atomic_int_compare_and_exchange(atomic, oldval, newval) \
   (G_GNUC_EXTENSION ({                                                       \
     gint gaicae_oldval = (oldval);                                           \
@@ -230,7 +230,7 @@ G_END_DECLS
     (guint) __atomic_fetch_xor ((atomic), (val), __ATOMIC_SEQ_CST);          \
   }))
 
-#if defined(glib_typeof) && defined(__cplusplus) && __cplusplus >= 201103L
+#if defined(glib_typeof) && defined(__cplusplus)
 /* This is typesafe because we check we can assign oldval to the type of
  * (*atomic). Unfortunately it can only be done in C++ because gcc/clang warn
  * when atomic is volatile and not oldval, or when atomic is gsize* and oldval
@@ -247,7 +247,7 @@ G_END_DECLS
     (void) (0 ? (gpointer) *(atomic) : NULL);                                \
     __atomic_compare_exchange_n ((atomic), &gapcae_oldval, (newval), FALSE, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST) ? TRUE : FALSE; \
   }))
-#else /* if !(defined(glib_typeof) && defined(__cplusplus) && __cplusplus >= 201103L) */
+#else /* if !(defined(glib_typeof) && defined(__cplusplus) */
 #define g_atomic_pointer_compare_and_exchange(atomic, oldval, newval) \
   (G_GNUC_EXTENSION ({                                                       \
     G_STATIC_ASSERT (sizeof (oldval) == sizeof (gpointer));                  \

glib/glib-typeof.h

@@ -34,9 +34,12 @@
  * This symbol is private.
  */
 #undef glib_typeof
-#if !defined(__cplusplus) && (G_GNUC_CHECK_VERSION(4, 8) || defined(__clang__))
+#if (!defined(__cplusplus) || (!defined (_MSVC_LANG) && __cplusplus < 201103L)) && \
+    (G_GNUC_CHECK_VERSION(4, 8) || defined(__clang__))
 #define glib_typeof(t) __typeof__ (t)
-#elif defined(__cplusplus) && __cplusplus >= 201103L && GLIB_VERSION_MIN_REQUIRED >= GLIB_VERSION_2_68
+#elif defined(__cplusplus) && \
+      (__cplusplus >= 201103L || (defined (_MSVC_LANG) && _MSVC_LANG > 201103L)) && \
+      GLIB_VERSION_MIN_REQUIRED >= GLIB_VERSION_2_68
 /* C++11 decltype() is close enough for our usage */
 #include <type_traits>
 #define glib_typeof(t) typename std::remove_reference<decltype (t)>::type

glib/tests/cxx.cpp

@@ -27,9 +27,6 @@ typedef struct
 static void
 test_typeof (void)
 {
-#if __cplusplus >= 201103L
-  // Test that with C++11 we don't get those kind of errors:
-  // error: invalid conversion from ‘gpointer’ {aka ‘void*’} to ‘MyObject*’ [-fpermissive]
   MyObject *obj = g_rc_box_new0 (MyObject);
   MyObject *obj2 = g_rc_box_acquire (obj);
   g_assert_true (obj2 == obj);
@@ -37,12 +34,21 @@ test_typeof (void)
   MyObject *obj3 = g_atomic_pointer_get (&obj2);
   g_assert_true (obj3 == obj);
 
+#if __cplusplus >= 201103L
   MyObject *obj4 = nullptr;
+#else
+  MyObject *obj4 = NULL;
+#endif
   g_atomic_pointer_set (&obj4, obj3);
   g_assert_true (obj4 == obj);
 
+#if __cplusplus >= 201103L
   MyObject *obj5 = nullptr;
   g_atomic_pointer_compare_and_exchange (&obj5, nullptr, obj4);
+#else
+  MyObject *obj5 = NULL;
+  g_atomic_pointer_compare_and_exchange (&obj5, NULL, obj4);
+#endif
   g_assert_true (obj5 == obj);
 
   MyObject *obj6 = g_steal_pointer (&obj5);
@@ -50,15 +56,11 @@ test_typeof (void)
 
   g_clear_pointer (&obj6, g_rc_box_release);
   g_rc_box_release (obj);
-#else
-  g_test_skip ("This test requires a C++11 compiler");
-#endif
 }
 
 static void
 test_atomic_pointer_compare_and_exchange (void)
 {
-#if __cplusplus >= 201103L
   const gchar *str1 = "str1";
   const gchar *str2 = "str2";
   const gchar *atomic_string = str1;
@@ -68,15 +70,11 @@ test_atomic_pointer_compare_and_exchange (void)
 
   g_assert_true (g_atomic_pointer_compare_and_exchange (&atomic_string, str1, str2));
   g_assert_true (atomic_string == str2);
-#else
-  g_test_skip ("This test requires a C++11 compiler");
-#endif
 }
 
 static void
 test_atomic_pointer_compare_and_exchange_full (void)
 {
-#if __cplusplus >= 201103L
   const gchar *str1 = "str1";
   const gchar *str2 = "str2";
   const gchar *atomic_string = str1;
@@ -88,15 +86,11 @@ test_atomic_pointer_compare_and_exchange_full (void)
   g_assert_true (g_atomic_pointer_compare_and_exchange_full (&atomic_string, str1, str2, &old));
   g_assert_true (atomic_string == str2);
   g_assert_true (old == str1);
-#else
-  g_test_skip ("This test requires a C++11 compiler");
-#endif
 }
 
 static void
 test_atomic_int_compare_and_exchange (void)
 {
-#if __cplusplus >= 201103L
   gint atomic_int = 5;
 
   g_test_message ("Test that g_atomic_int_compare_and_exchange() doesn’t have "
@@ -104,15 +98,11 @@ test_atomic_int_compare_and_exchange (void)
 
   g_assert_true (g_atomic_int_compare_and_exchange (&atomic_int, 5, 50));
   g_assert_cmpint (atomic_int, ==, 50);
-#else
-  g_test_skip ("This test requires a C++11 compiler");
-#endif
 }
 
 static void
 test_atomic_int_compare_and_exchange_full (void)
 {
-#if __cplusplus >= 201103L
   gint atomic_int = 5;
   gint old_value;
 
@@ -122,15 +112,11 @@ test_atomic_int_compare_and_exchange_full (void)
   g_assert_true (g_atomic_int_compare_and_exchange_full (&atomic_int, 5, 50, &old_value));
   g_assert_cmpint (atomic_int, ==, 50);
   g_assert_cmpint (old_value, ==, 5);
-#else
-  g_test_skip ("This test requires a C++11 compiler");
-#endif
 }
 
 static void
 test_atomic_pointer_exchange (void)
 {
-#if __cplusplus >= 201103L
   const gchar *str1 = "str1";
   const gchar *str2 = "str2";
   const gchar *atomic_string = str1;
@@ -140,24 +126,17 @@ test_atomic_pointer_exchange (void)
 
   g_assert_true (g_atomic_pointer_exchange (&atomic_string, str2) == str1);
   g_assert_true (atomic_string == str2);
-#else
-  g_test_skip ("This test requires a C++11 compiler");
-#endif
 }
 
 static void
 test_atomic_int_exchange (void)
 {
-#if __cplusplus >= 201103L
   gint atomic_int = 5;
 
   g_test_message ("Test that g_atomic_int_compare_and_exchange() doesn’t have "
                   "any compiler warnings in C++ mode");
 
   g_assert_cmpint (g_atomic_int_exchange (&atomic_int, 50), ==, 5);
-#else
-  g_test_skip ("This test requires a C++11 compiler");
-#endif
 }
 
 G_NO_INLINE
@@ -184,6 +163,35 @@ test_inline_no_inline_macros (void)
   g_assert_true (do_inline_this ());
 }
 
+static void
+clear_boolean_ptr (gboolean *val)
+{
+  *val = TRUE;
+}
+
+static void
+test_clear_pointer (void)
+{
+  gboolean value = FALSE;
+  gboolean *ptr = &value;
+
+  g_assert_true (ptr == &value);
+  g_assert_false (value);
+  g_clear_pointer (&ptr, clear_boolean_ptr);
+  g_assert_null (ptr);
+  g_assert_true (value);
+}
+
+static void
+test_steal_pointer (void)
+{
+  gpointer ptr = &ptr;
+
+  g_assert_true (ptr == &ptr);
+  g_assert_true (g_steal_pointer (&ptr) == &ptr);
+  g_assert_null (ptr);
+}
+
 int
 main (int argc, char *argv[])
 {
@@ -201,6 +209,8 @@ main (int argc, char *argv[])
   g_test_add_func ("/C++/atomic-pointer-exchange", test_atomic_pointer_exchange);
   g_test_add_func ("/C++/atomic-int-exchange", test_atomic_int_exchange);
   g_test_add_func ("/C++/inlined-not-inlined-functions", test_inline_no_inline_macros);
+  g_test_add_func ("/C++/clear-pointer", test_clear_pointer);
+  g_test_add_func ("/C++/steal-pointer", test_steal_pointer);
 
   return g_test_run ();
 }

glib/tests/meson.build

@@ -159,8 +159,19 @@ if have_cxx
   glib_tests += {
     'cxx' : {
       'source' : ['cxx.cpp'],
+      'suite': ['cpp'],
     }
   }
+
+  foreach std, arg: cxx_standards
+    glib_tests += {
+      'cxx-@0@'.format(std) : {
+        'source' : ['cxx.cpp'],
+        'suite' : ['cpp'],
+        'cpp_args' : [arg],
+      },
+    }
+  endforeach
 endif
 
 if cc.get_id() != 'msvc'
@@ -255,6 +266,7 @@ test_env.set('MALLOC_CHECK_', '2')
 
 test_deps = [libm, thread_dep, libglib_dep]
 test_cargs = ['-DG_LOG_DOMAIN="GLib"', '-UG_DISABLE_ASSERT']
+test_cpp_args = test_cargs
 
 foreach test_name, extra_args : glib_tests
   source = extra_args.get('source', test_name + '.c')
@@ -276,6 +288,7 @@ foreach test_name, extra_args : glib_tests
 
   exe = executable(test_name, source,
     c_args : test_cargs + extra_args.get('c_args', []),
+    cpp_args : test_cpp_args + extra_args.get('cpp_args', []),
     link_args : extra_args.get('link_args', []),
     dependencies : test_deps + extra_args.get('dependencies', []),
     install_dir: installed_tests_execdir,

gmodule/tests/meson.build

@@ -15,8 +15,19 @@ if have_cxx
   gmodule_tests += {
     'cxx' : {
       'source' : ['cxx.cpp'],
+      'suite' : ['cpp'],
     }
   }
+
+  foreach std, arg: cxx_standards
+    gmodule_tests += {
+      'cxx-@0@'.format(std) : {
+        'source' : ['cxx.cpp'],
+        'suite' : ['cpp'],
+        'cpp_args' : [arg],
+      },
+    }
+  endforeach
 endif
 
 module_suffix = []
@@ -51,6 +62,7 @@ test_env.set('MALLOC_CHECK_', '2')
 
 test_deps = [libm, thread_dep, libglib_dep, libgmodule_dep]
 test_cargs = ['-DG_LOG_DOMAIN="GModule"', '-UG_DISABLE_ASSERT']
+test_cpp_args = test_cargs
 
 foreach test_name, extra_args : gmodule_tests
   source = extra_args.get('source', test_name + '.c')
@@ -72,6 +84,7 @@ foreach test_name, extra_args : gmodule_tests
 
   exe = executable(test_name, source,
     c_args : test_cargs + extra_args.get('c_args', []),
+    cpp_args : test_cpp_args + extra_args.get('cpp_args', []),
     link_args : extra_args.get('link_args', []),
     dependencies : test_deps + extra_args.get('dependencies', []),
     export_dynamic : extra_args.get('export_dynamic', false),

gobject/tests/meson.build

@@ -102,8 +102,19 @@ if have_cxx
   gobject_tests += {
     'cxx' : {
       'source' : ['cxx.cpp'],
+      'suite' : ['cpp'],
     },
   }
+
+  foreach std, arg: cxx_standards
+    gobject_tests += {
+      'cxx-@0@'.format(std) : {
+        'source' : ['cxx.cpp'],
+        'suite' : ['cpp'],
+        'cpp_args' : [arg],
+      },
+    }
+  endforeach
 endif
 
 if cc.get_id() != 'msvc'
@@ -125,6 +136,7 @@ test_env.set('MALLOC_CHECK_', '2')
 
 test_deps = [libm, thread_dep, libglib_dep, libgobject_dep]
 test_cargs = ['-DG_LOG_DOMAIN="GLib-GObject"', '-UG_DISABLE_ASSERT']
+test_cpp_args = test_cargs
 
 foreach test_name, extra_args : gobject_tests
   source = extra_args.get('source', test_name + '.c')
@@ -146,6 +158,7 @@ foreach test_name, extra_args : gobject_tests
 
   exe = executable(test_name, source,
     c_args : test_cargs + extra_args.get('c_args', []),
+    cpp_args : test_cpp_args + extra_args.get('cpp_args', []),
     dependencies : test_deps + extra_args.get('dependencies', []),
     install_dir: installed_tests_execdir,
     install_tag: 'tests',

meson.build

@@ -13,6 +13,14 @@ cc = meson.get_compiler('c')
 have_cxx = add_languages('cpp', native: false, required: get_option('oss_fuzz').enabled())
 if have_cxx
   cxx = meson.get_compiler('cpp')
+  cxx_standards = {}
+
+  foreach std : ['98', '03', '11', '14', '17', '20', '2b', 'latest']
+    arg = (cxx.get_id() == 'msvc' ? '/std:' : '-std=') + 'c++' + std
+    if cxx.has_argument(arg)
+      cxx_standards += { std: arg }
+    endif
+  endforeach
 endif
 
 cc_can_run = meson.can_run_host_binaries()