+// as wxCHECK but with a message explaining why we fail
+#define wxCHECK_MSG(x, rc, msg) if (!(x)) {wxFAIL_MSG(msg); return rc; }
+
+// check that expression is true, perform op if not
+#define wxCHECK2(x, op) if (!(x)) {wxFAIL; op; }
+
+// as wxCHECK2 but with a message explaining why we fail
+#define wxCHECK2_MSG(x, op, msg) if (!(x)) {wxFAIL_MSG(msg); op; }
+
+// special form of wxCHECK2: as wxCHECK, but for use in void functions
+//
+// NB: there is only one form (with msg parameter) and it's intentional:
+// there is no other way to tell the caller what exactly went wrong
+// from the void function (of course, the function shouldn't be void
+// to begin with...)
+#define wxCHECK_RET(x, msg) if (!(x)) {wxFAIL_MSG(msg); return; }
+
+// ----------------------------------------------------------------------------
+// Compile time asserts
+//
+// Unlike the normal assert and related macros above which are checked during
+// the program tun-time the macros below will result in a compilation error if
+// the condition they check is false. This is usually used to check the
+// expressions containing sizeof()s which cannot be tested with the
+// preprocessor. If you can use the #if's, do use them as you can give a more
+// detailed error message then.
+// ----------------------------------------------------------------------------
+
+/*
+ How this works (you don't have to understand it to be able to use the
+ macros): we rely on the fact that it is invalid to define a named bit field
+ in a struct of width 0. All the rest are just the hacks to minimize the
+ possibility of the compiler warnings when compiling this macro: in
+ particular, this is why we define a struct and not an object (which would
+ result in a warning about unused variable) and a named struct (otherwise we'd
+ get a warning about an unnamed struct not used to define an object!).
+ */
+
+#define wxMAKE_ASSERT_NAME_HELPER(line) wxAssert_ ## line
+#define wxMAKE_ASSERT_NAME(line) wxMAKE_ASSERT_NAME_HELPER(line)
+#define wxMAKE_UNIQUE_ASSERT_NAME wxMAKE_ASSERT_NAME(__LINE__)
+#define wxMAKE_UNIQUE_ASSERT_NAME2(text) wxMAKE_ASSERT_NAME(text)
+
+/*
+ The second argument of this macro must be a valid C++ identifier and not a
+ string. I.e. you should use it like this:
+
+ wxCOMPILE_TIME_ASSERT( sizeof(int) >= 2, YourIntsAreTooSmall );
+
+ It may be used both within a function and in the global scope.