diff --git a/cfg/gtk.cfg b/cfg/gtk.cfg
index 2d793484c..ed694398e 100644
--- a/cfg/gtk.cfg
+++ b/cfg/gtk.cfg
@@ -2965,13 +2965,31 @@
     <leak-ignore/>
     <noreturn>false</noreturn>
   </function>
+  <!-- gboolean g_once_init_enter (volatile void *location); -->
   <function name="g_once_init_enter">
     <leak-ignore/>
     <noreturn>false</noreturn>
+    <returnValue type="gboolean"/>
+    <use-retval/>
+    <arg nr="1">
+      <not-null/>
+      <not-uninit/>
+    </arg>
   </function>
+  <!-- void g_once_init_leave (volatile void *location,
+                               gsize result); -->
   <function name="g_once_init_leave">
     <leak-ignore/>
     <noreturn>false</noreturn>
+    <returnValue type="void"/>
+    <arg nr="1">
+      <not-null/>
+      <not-uninit/>
+    </arg>
+    <arg nr="2" direction="in">
+      <not-uninit/>
+      <valid>1:</valid>
+    </arg>
   </function>
   <function name="g_option_error_quark">
     <leak-ignore/>
@@ -19650,6 +19668,24 @@
       <not-uninit/>
     </arg>
   </function>
+  <!-- void g_signal_emit_by_name (gpointer instance,
+                                   const gchar *detailed_signal,
+                                   ...); -->
+  <function name="g_signal_emit_by_name">
+    <noreturn>false</noreturn>
+    <returnValue type="void"/>
+    <leak-ignore/>
+    <arg nr="1">
+      <not-uninit/>
+    </arg>
+    <arg nr="2" direction="in">
+      <not-uninit/>
+      <strz/>
+    </arg>
+    <arg nr="variadic">
+      <not-uninit/>
+    </arg>
+  </function>
   <define name="gchar" value="char"/>
   <define name="guchar" value="unsigned char"/>
   <define name="gint" value="int"/>
diff --git a/test/cfg/gtk.c b/test/cfg/gtk.c
index b0d6bcb4a..e89d90854 100644
--- a/test/cfg/gtk.c
+++ b/test/cfg/gtk.c
@@ -53,6 +53,12 @@ void validCode(int argInt)
 
     GError * pGerror = g_error_new(1, -2, "a %d", 1);
     g_error_free(pGerror);
+
+    static gsize init_val = 0;
+    if (g_once_init_enter(&init_val)) {
+        gsize result_val = 1;
+        g_once_init_leave(&init_val, result_val);
+    }
 }
 
 void g_malloc_test()
@@ -366,3 +372,32 @@ void g_error_new_test()
     printf("%p", pNew2);
     // cppcheck-suppress memleak
 }
+
+void g_once_init_enter_leave_test()
+{
+    static gsize init_val;
+    if (g_once_init_enter(&init_val)) {
+        gsize result_val = 0;
+        // cppcheck-suppress invalidFunctionArg
+        g_once_init_leave(&init_val, result_val);
+    }
+
+    gsize init_val2;
+    // cppcheck-suppress uninitvar
+    // cppcheck-suppress ignoredReturnValue
+    g_once_init_enter(&init_val2);
+
+    gsize * init_val3 = NULL;
+    // cppcheck-suppress nullPointer
+    if (g_once_init_enter(init_val3)) {
+        // cppcheck-suppress nullPointer
+        g_once_init_leave(init_val3, 1);
+    }
+
+    gsize * init_val4;
+    // cppcheck-suppress uninitvar
+    if (g_once_init_enter(init_val4)) {
+        // cppcheck-suppress uninitvar
+        g_once_init_leave(init_val4, 1);
+    }
+}