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=== Pointers and references ===
For pointer and reference types, the meaning of <code>const</code> is more complicated – either the pointer itself, or the value being pointed to, or both, can be <code>const</code>. Further, the syntax can be confusing. A pointer can be declared as a <code>const</code> pointer to writable value, or a writable pointer to a <code>const</code> value, or <code>const</code> pointer to <code>const</code> value. {{anchor|Pointee|Cray pointer}}A <code>const</code> pointer cannot be reassigned to point to a different object from the one it is initially assigned, but it can be used to modify the value that it points to (called the ''pointee'').<ref>{{cite book |title=The GNU Fortran Compiler |chapter=5.1. Extensions implemented in GNU Fortran: 5.1.16 Cray pointers |date=2006 |url=https://gcc.gnu.org/onlinedocs/gfortran/Cray-pointers.html#Cray-pointers |access-date=2022-12-21 |url-status=live |archive-url=https://web.archive.org/web/20221221175054/https://gcc.gnu.org/onlinedocs/gfortran/Cray-pointers.html#Cray-pointers |archive-date=2022-12-21}}</ref> Reference variables in C++ are an alternate syntax for <code>const</code> pointers. A pointer to a <code>const</code> object, on the other hand, can be reassigned to point to another memory ___location (which should be an object of the same type or of a convertible type), but it cannot be used to modify the memory that it is pointing to. A <code>const</code> pointer to a <code>const</code> object can also be declared and can neither be used to modify the pointee nor be reassigned to point to another object. The following code illustrates these subtleties:
<syntaxhighlight lang=c>
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