macros.h 3/5: Split various macros (#2512)

* split out various macros

* fix

* fix2

* fix dw

* libc path

* fix macro

* does this fix bss

* fix bss

include/avoid_ub.h

@@ -0,0 +1,13 @@
+#ifndef AVOID_UB_H
+#define AVOID_UB_H
+
+/**
+ * This macro is used when the return type of a function is incorrect
+ */
+#ifndef AVOID_UB
+#define BAD_RETURN(type) type
+#else
+#define BAD_RETURN(type) void
+#endif
+
+#endif