test: silence an infinite-loop error in g_error()

Due to some improvements to GCC's static analyzer, the intentional
loop in `g_error()` throws an error in the CI.

Add `V_GNUC_BEGIN_IGNORE_INFINITE_LOOP` (and matching `END`) macro to
silence false positives from `g_error()`.

src/libvalent/core/valent-debug.h.in

@@ -204,5 +204,40 @@ void valent_trace_mark (const char *strfunc,
 # define VALENT_JSON(_node, _ctx)      G_STMT_START {          } G_STMT_END
 #endif
 
+/**
+ * V_GNUC_BEGIN_IGNORE_INFINITE_LOOP: (skip)
+ *
+ * Tells gcc (if it is a new enough version) to temporarily stop emitting
+ * warnings when functions employ an infinite loop. This is useful for functions
+ * that do so intentionally, such as [[email protected]].
+ *
+ * Since: 1.0
+ */
+
+/**
+ * V_GNUC_END_IGNORE_INFINITE_LOOP: (skip)
+ *
+ * Undoes the effect of [[email protected]_GNUC_BEGIN_IGNORE_INFINITE_LOOP], telling gcc
+ * to begin outputting warnings again (assuming those warnings had been enabled
+ * to begin with).
+ *
+ * Since: 1.0
+ */
+
+#if G_GNUC_CHECK_VERSION(14, 0)
+  #define V_GNUC_BEGIN_IGNORE_INFINITE_LOOP                          \
+    G_STMT_START {                                                   \
+      _Pragma("GCC diagnostic push")                                 \
+      _Pragma("GCC diagnostic ignored \"-Wanalyzer-infinite-loop\"") \
+    } G_STMT_END
+  #define V_GNUC_END_IGNORE_INFINITE_LOOP                            \
+    G_STMT_START {                                                   \
+      _Pragma("GCC diagnostic pop")                                  \
+    } G_STMT_END
+#else
+  #define V_GNUC_BEGIN_IGNORE_INFINITE_LOOP G_STMT_START { } G_STMT_END
+  #define V_GNUC_END_IGNORE_INFINITE_LOOP   G_STMT_START { } G_STMT_END
+#endif
+
 G_END_DECLS
 

src/libvalent/core/valent-object.c

@@ -6,6 +6,7 @@
 
 #include "config.h"
 
+#include "valent-debug.h"
 #include "valent-macros.h"
 #include "valent-object.h"
 
@@ -182,9 +183,13 @@ static void
 valent_object_constructed (GObject *object)
 {
   if G_UNLIKELY (G_OBJECT_GET_CLASS (object)->dispose != valent_object_dispose)
-    g_error ("%s overrides GObject.Object.dispose() instead of "
-             "Valent.Object.destroy(), which is not thread safe",
-             G_OBJECT_TYPE_NAME (object));
+    {
+      V_GNUC_BEGIN_IGNORE_INFINITE_LOOP;
+      g_error ("%s overrides GObject.Object.dispose() instead of "
+               "Valent.Object.destroy(), which is not thread safe",
+               G_OBJECT_TYPE_NAME (object));
+      V_GNUC_END_IGNORE_INFINITE_LOOP;
+    }
 
   G_OBJECT_CLASS (valent_object_parent_class)->constructed (object);
 }