No warning when assigning 'const int' to 'int'

Question

In the subsection 'Simple Assignment' of spec, it has the constraint

• the left operand has qualified or unqualified arithmetic type and the right has arithmetic type

It seems that the following code snippet violates this but clang -Weverything doesn't give any warnings. What am I interpreting wrong?

const int i = 5;
int j = i;

Answer 1

Integer assignment is done by value. const int means that the 4 (or 8) bytes of that int are read-only. Assignment just copies the bytes of i into another location specified by j . This involves reading i and writing to j , both of which are declared as valid operations.

Answer 2

Your code doesn't perform any assignment, so it does not violate any rules about assignment.

(Your code is a declaration with initialization.)

Answer 3

try i=j; you will see. gcc give you this: "error: assignment of read-only variable"