diff --git a/cfg/gnu.cfg b/cfg/gnu.cfg
index 4aeb309d1..97f562b75 100644
--- a/cfg/gnu.cfg
+++ b/cfg/gnu.cfg
@@ -46,6 +46,7 @@
   <define name="__builtin_nanf(str)" value="nanf(str)"/>
   <define name="__builtin_nanl(str)" value="nanl(str)"/>
   <define name="__builtin_signbit(value)" value="signbit(value)"/>
+  <define name="__extension__" value=""/>
   <!-- void *__builtin_alloca (size_t size) -->
   <!-- alloca() is often defined as __builtin_alloca() so the define above does not work always -->
   <!-- void *alloca(size_t size); -->
diff --git a/test/cfg/gnu.c b/test/cfg/gnu.c
index d97f6e459..f4895e16e 100644
--- a/test/cfg/gnu.c
+++ b/test/cfg/gnu.c
@@ -137,6 +137,9 @@ void valid_code(int argInt1, va_list valist_arg)
     if (vasprintf(&pStr, "%d %d", valist_arg) != -1) {
         free(pStr);
     }
+
+    printf("%d", 0b010);
+    printf("%d", __extension__ 0b10001000);
 }
 
 void ignoreleak(void)