Fix build on MSVC
diff --git a/pb.h b/pb.h
index 644a759..01320c7 100644
--- a/pb.h
+++ b/pb.h
@@ -183,6 +183,9 @@
 #  define PB_STATIC_ASSERT(COND,MSG)
 #endif
 
+/* Test that PB_STATIC_ASSERT works */
+PB_STATIC_ASSERT(1, STATIC_ASSERT_IS_NOT_WORKING)
+
 /* Number of required fields to keep track of. */
 #ifndef PB_MAX_REQUIRED_FIELDS
 #define PB_MAX_REQUIRED_FIELDS 64
diff --git a/tests/SConstruct b/tests/SConstruct
index b2b8b36..0c17460 100644
--- a/tests/SConstruct
+++ b/tests/SConstruct
@@ -192,6 +192,9 @@
         # More strict checks on the nanopb core
         env.Append(CORECFLAGS = '/W4')
 
+        # Enable C11 standard
+        env.Append(CFLAGS = ' /std:c11 ')
+
         # Disable warning about sizeof(union{}) construct that is used in
         # message size macros, in e.g. multiple_files testcase. The C construct
         # itself is valid, but quite rare, which causes Visual C++ to give a warning