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/*
** !!DESCRIPTION!! Simple tests of pointer-to-array dereferences
** !!ORIGIN!! cc65 regression tests
** !!LICENCE!! Public Domain
** !!AUTHOR!! 2015-06-29, Greg King
*/
#include <stdio.h>
static unsigned char failures = 0;
static size_t Size;
typedef unsigned char array_t[4][4];
static array_t table = {
{12, 13, 14, 15},
{ 8, 9, 10, 11},
{ 4, 5, 6, 7},
{ 0, 1, 2, 3}
};
static array_t *tablePtr = &table;
static unsigned (*vector)[2];
static unsigned char y = 0, x;
int main(void)
{
/* The indirection must convert the expression-type (from Pointer into
** Array); but, it must not convert the value, because it already points
** to the start of the array.
*/
/* (Note: I reduce output clutter by using a variable to prevent
** compiler warnings about constant comparisons and unreachable code.
*/
if ((Size = sizeof *tablePtr) != sizeof table) {
++failures;
}
if (*tablePtr != table) {
++failures;
}
/* Test fetching. */
do {
x = 0;
do {
if ((*tablePtr)[y][x] != table[y][x]) {
++failures;
printf("(*tableptr)[%u][%u] (%u) != table[%u][%u] (%u).\n",
y, x, (*tablePtr)[y][x],
y, x, table[y][x]);
}
} while (++x < sizeof table[0]);
} while (++y < sizeof table / sizeof table[0]);
vector = (unsigned (*)[])table[1];
if ((*vector)[1] != 0x0B0A) {
++failures;
}
/* Test storing. */
(*tablePtr)[2][1] = 42;
if (table[2][1] != 42) {
++failures;
printf("table[2][1] == %u (should have changed from 5 to 42).\n",
table[2][1]);
}
x = 3;
y = 1;
(*tablePtr)[y][x] = 83;
if (table[1][3] != 83) {
++failures;
printf("table[y][x] == %u (should have changed from 11 to 83).\n",
table[1][3]);
}
/* Test triple indirection. It should compile to two indirection
** operations.
*/
--***tablePtr;
if (**table != 11) {
++failures;
printf("**table == %u (should have changed from 12 to 11).\n",
table[0][0]);
}
if (failures != 0) {
printf("failures: %u\n", failures);
}
return failures;
}
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