diff --git a/gio/tests/meson.build b/gio/tests/meson.build
index 16478f69b..e0bcc7c72 100644
--- a/gio/tests/meson.build
+++ b/gio/tests/meson.build
@@ -144,6 +144,7 @@ gio_tests = {
 if have_cxx
   gio_tests += {
     'cxx' : {
+      'protocol': 'exitcode',
       'source' : ['cxx.cpp'],
       'suite': ['C++'],
     },
@@ -152,6 +153,7 @@ if have_cxx
   foreach std, arg: cxx_standards
     gio_tests += {
       'cxx-@0@'.format(std) : {
+        'protocol': 'exitcode',
         'source' : ['cxx.cpp'],
         'suite' : ['cpp'],
         'cpp_args' : [arg],
diff --git a/gmodule/tests/meson.build b/gmodule/tests/meson.build
index 513ea4213..ec7eb68fd 100644
--- a/gmodule/tests/meson.build
+++ b/gmodule/tests/meson.build
@@ -5,6 +5,7 @@ gmodule_tests = {
 if have_cxx
   gmodule_tests += {
     'cxx' : {
+      'protocol': 'exitcode',
       'source' : ['cxx.cpp'],
       'suite' : ['cpp'],
     }
@@ -13,6 +14,7 @@ if have_cxx
   foreach std, arg: cxx_standards
     gmodule_tests += {
       'cxx-@0@'.format(std) : {
+        'protocol': 'exitcode',
         'source' : ['cxx.cpp'],
         'suite' : ['cpp'],
         'cpp_args' : [arg],
diff --git a/gobject/tests/meson.build b/gobject/tests/meson.build
index 96a7b40d3..9e807463b 100644
--- a/gobject/tests/meson.build
+++ b/gobject/tests/meson.build
@@ -41,7 +41,7 @@ gobject_tests = {
   'defaultiface' : {
     'source' : ['defaultiface.c', 'testmodule.c'],
   },
-  'deftype' : {},
+  'deftype' : { 'protocol': 'exitcode' },
   'deprecated-properties' : {},
   'dynamictype' : {
     'source' : ['dynamictype.c', 'testmodule.c'],
@@ -109,6 +109,7 @@ gobject_tests = {
 if have_cxx
   gobject_tests += {
     'cxx' : {
+      'protocol': 'exitcode',
       'source' : ['cxx.cpp'],
       'suite' : ['cpp'],
     },
@@ -117,6 +118,7 @@ if have_cxx
   foreach std, arg: cxx_standards
     gobject_tests += {
       'cxx-@0@'.format(std) : {
+        'protocol': 'exitcode',
         'source' : ['cxx.cpp'],
         'suite' : ['cpp'],
         'cpp_args' : [arg],