c - Byte-addressed memory (Data alignment) -

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i don't want homework. want tips on how can learn myself.

given byte-addressed memory writes lowest highest addresses. have c program has following declarations:

long int = 1; char c = 'x'; short int n = 10; short in m = 11; float f = 0.0;

in ia32 int 4 bytes, char 1 byte, short 2 byte , float 4 byte. how these declaration saved in memory likely? fill out following in hex digits.

enter image description here

how begin here? can give me tips? what's first thing have do?

edit: prof told me system ia32.

i assume variables declared , defined local (not static/global) variables, example:

int main() {     long int = 1;     char c = 'x';     short int n = 10;     short in m = 11;     float f = 0.0; }

if so, allocated on stack.

the principles of allocating local variables on stack same systems:

  1. stack grows high addresses low addresses
  2. the order of declaration of variables in program corresponds growth of stack
  3. each type has alignment - address of variable must divisible size (1 char, 2 short, etc)
  4. try waste little space possible

there conflict between principles (2) , (4) - if rearranging variables saves space, compiler it? guess can assume no (this "most likely" part in question).

the real situation more complicated (sizeof not prescribed above numbers; alignment requirement not equal sizeof; compiler may reuse space 2 different variables; etc) - have simplify if want solve homework in reasonable amount of time.


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