gdb: C Checks

 
 15.4.1.5 C and C++ Type and Range Checks
 ........................................
 
 By default, when GDB parses C or C++ expressions, strict type checking
 is used.  However, if you turn type checking off, GDB will allow certain
 non-standard conversions, such as promoting integer constants to
 pointers.
 
    Range checking, if turned on, is done on mathematical operations.
 Array indices are not checked, since they are often used to index a
 pointer that is not itself an array.