the same memory location can have different values

[James Kanze]

"The result is implementation-defined if an attempt is made to
change a const." from "The C programming language" by Brian
Kernighan, Dennis Ritchie

The result is undefined behavior if an attempt is made to change
a const. From the C and the C++ standards.

 

[Floare Augustin Theodor]

The case of changing a const is discussed here:
http://www.safercode.com/blog/2009/02/04/const-keyword-explained.html

Regards,
Teo

 

[Bo Persson]

The case of changing a const is discussed here:
http://www.safercode.com/blog/2009/02/04/const-keyword-explained.html

Regards,
Teo

And that text is just incorrect. The part where it says:

const int a = 1;
int *b = &a;
is invalid code. The "trick" of ignoring the warning or using an
invalid type cast, doesn't make it valid.Bo Persson