source: doc/theses/mike_brooks_MMath/programs/bkgd-carray-mdim.c@ 77328d0

Last change on this file since 77328d0 was df699e0, checked in by Peter A. Buhr <pabuhr@…>, 16 months ago

program updates to match text

  • Property mode set to 100644
File size: 1.4 KB
Line 
1#include <stdio.h>
2#include <assert.h>
3#include <stdlib.h>
4
5#define SHOW(x, fmt) printf( #x ": " fmt "\n", x )
6
7#ifdef ERRS
8#define ERR(...) __VA_ARGS__
9#else
10#define ERR(...)
11#endif
12
13
14
15int main() {
16 float ar[3][10];
17 static_assert(sizeof(float) == 4); $\C{// floats (atomic elements) are 4 bytes}$
18 static_assert(sizeof(void*) == 8); $\C{// pointers are 8 bytes}$
19
20 static_assert(sizeof(ar) == 120); $\C{// the array, float[3][10]}$
21 static_assert(sizeof(ar[0]) == 40); $\C{// its first element, float[10]}$
22 static_assert(sizeof(ar[0][0]) == 4); $\C{// its first grand element, float}$
23
24 static_assert(sizeof(&(ar)) == 8); $\C{// pointer to the array, float(*)[3][10]}$
25 static_assert(sizeof(&(ar[0])) == 8); $\C{// pointer to its first element, float(*)[10]}$
26 static_assert(sizeof(&(ar[0][0])) == 8); $\C{// pointer to its first grand-element, float*}$
27
28 float (*pa)[3][10] = &(ar);
29 float (*pa0)[10] = &(ar[0]);
30 float *pa00 = &(ar[0][0]);
31
32 static_assert((void*)&ar == (void*)&(ar[0] ));
33 static_assert((void*)&ar == (void*)&(ar[0][0]));
34
35 assert( (void *) pa == (void *) pa0 );
36 assert( (void *) pa == (void *) pa00 );
37
38// float (*b[3])[10];
39 float *b[3];
40 for (int i = 0; i < 3; i ++) {
41 b[i] = malloc(sizeof(float[10]));
42 }
43 ar[2][3];
44 b[2][3];
45/*
46
47*/
48
49}
50
51// Local Variables: //
52// compile-command: "sed -f sedcmd bkgd-carray-mdim.c | gcc-11 -Wall -Wextra -x c -" //
53// End: //
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