1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 | #include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <assert.h>
// okay to copy/adapt these macros
#define log_int(n) printf("%s == %d\n", (#n), n)
#define log_addr(n) printf("%s == %p\n", (#n), (void*)n)
// broken: only swaps the values of the arguments of swap
// not the original variables
void swap(int left, int right) {
int left_orig = left;
left = right;
right = left_orig;
}
int main(int argc, char* argv[]) {
int n1 = 5;
int n2 = 27;
log_int(n1);
log_int(n2);
swap(n1, n2);
// swap((long)&n1, (long)&n2); // fixes warning, but not the bug
/*
e_swap_bad_1.c: In function ‘main’:
e_swap_bad_1.c:24:7: warning: passing argument 1 of ‘swap’ makes integer from pointer without a cast [-Wint-conversion]
swap(&n1, &n2);
^~~
e_swap_bad_1.c:10:15: note: expected ‘int’ but argument is of type ‘int *’
void swap(int left, int right) {
~~~~^~~~
e_swap_bad_1.c:24:12: warning: passing argument 2 of ‘swap’ makes integer from pointer without a cast [-Wint-conversion]
swap(&n1, &n2);
^~~
e_swap_bad_1.c:10:25: note: expected ‘int’ but argument is of type ‘int *’
void swap(int left, int right) {
~~~~^~~~~
*/
printf("Swap called\n");
log_int(n1);
log_int(n2);
return EXIT_SUCCESS;
}
/* vim: set tabstop=4 shiftwidth=4 fileencoding=utf-8 noexpandtab: */
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