process memory structure, C++ (gcc)

process memory structure

// Example program
//g++  5.4.0

#include <cstdio>

//const expression
constexpr const int const1 = 1;
constexpr const int const2 = 2;

// bss section
int global1;
int global2 = 0;

// data section
int  global_init1 = 1;
int  global_init2 = 1;

// 
namespace Space{
    int spaceB = 0; // bss
    int spaceD = 1; // data
};

// text section, data section
void test1(){
    // [text] expression
    printf("expr 1  addr : %p \n", &const1 );
    printf("expr 2  addr : %p \n", &const2 );
    // [bss] uninited data
    printf("global1 addr : %p \n", &global1 );
    printf("global2 addr : %p \n", &global2 );
    printf("spaceBS addr : %p \n", &Space::spaceB);
    // [data] inited data
    printf("inited1 addr : %p \n", &global_init1 );
    printf("inited2 addr : %p \n", &global_init2 );
    printf("spaceDA addr : %p \n", &Space::spaceD);
}

// stack
void test2(){
    int local1;
    int local2;
    int local3;

printf("local1  addr : %p \n", &local1);
    printf("local2  addr : %p \n", &local2);
    printf("local3  addr : %p \n", &local3);
}

// stack
void test3(){
    int local1;
    int local2;
    int local3;
    int local[3];

printf("local1   addr : %p \n" , &local1);
    printf("local2   addr : %p \n" , &local2);
    printf("local3   addr : %p \n" , &local3);

printf("local[2] addr : %p \n" , local+2);
    printf("local[1] addr : %p \n" , local+1);
    printf("local[0] addr : %p \n" , local);
}

// stack
void test4(){
    int local1;
    int local2;
    int local3;

printf("local1  addr : %p \n", &local1);
    printf("local2  addr : %p \n", &local2);
    printf("local3  addr : %p \n", &local3);
}

// heap
void test5(){
    int* local1 = new int(0);
    int* local2 = new int(0);
    int* local3 = new int(0);

printf("local1  addr : %p \n", local1);
    printf("local2  addr : %p \n", local2);
    printf("local3  addr : %p \n", local3);

delete local1;
    delete local2;
    delete local3;
}

// test each function
typedef void (*VFP)();
void test(const char* name, VFP fp){
    printf("%s addr : %p \n", name , fp);
    fp();
    printf("\n");
}

int main()
{
    printf("main  addr : %p \n\n",main);

test("test1()" , test1); // print : text section, data section, namespace
    test("test2()" , test2); // print : stack
    test("test3()" , test3); // print : stack, array
    test("test4()" , test4); // print : stack
    test("test5()" , test5); // print : heap

return 0;
}

// stack section grow up not down

// but compile on cpp.sh and code::block without Optimization
// stack section grow down

// with Optimization
// stack section grow up
// why ??


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