c++ - can anyone explain where the constants or const variables stored? -


as know, c++'s memory model can divided 5 blocks: stack, heap, free blocks, global/static blocks, const blocks. can understand first 3 blocks , know variables static int xx stored in 4th blocks, , "hello world"-string constant, stored in 5th blocks-const blocks? , , int = 10, "10" stored? can explain me?

thanks lot.

there difference between string literals , primitive constants. string literals stored code in separate area (for historical reasons block called "text block"). primitive constants, on other hand, special: can stored in "text" block well, values can "baked" code itself. example, when write

// global integer constant const int = 10;  int add(int b) {     return b + a; }

the return expression translated piece of code not reference a @ all. instead of producing binary code looks this

load r0, <stack>+offset(b) load r1, <address-of-a> add r0, r1 ret

the compiler may produce this:

load r0, <stack>+offset(b) add r0, #10 ; <<== here #10 means "integer number 10" ret

essentially, despite being stored rest of constants, a cut out of compiled code.

as far integer literals constants go, have no address @ all: "baked" code: when reference them, instructions load explicit values generated, in same way shown above.


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