gcc/testsuite/gcc.dg/pack-test-1.c

   1 /* Test semantics of #pragma pack.
   2    Contributed by Mike Coleman <mcoleman2@kc.rr.com> */
   3
   4 /* { dg-do compile { target { ! default_packed } } } */
   5
   6 /* Mainly we're just testing whether pushing and popping seem to be
   7    working correctly, and verifying the (alignment == 1) case, which
   8    is really the only reason anyone would use this pragma anyway. */
   9
  10 #include <stddef.h>
  11
  12 /* generalized compile-time test expression */
  13 #define test(n, expr) int test_##n [(expr) ? 1 : -1]
  14
  15 /* Round V down to multiple of A */
  16 #define floor(v,a) ((v) / (a) * (a))
  17
  18 /* Offset of field with alignment A in structure S after a field P of
  19    type PT */
  20 #define offset(s,p,pt,a) \
  21         floor ((offsetof(struct s, p) + sizeof (pt) + (a) - 1), a)
  22
  23 /* regular minimum */
  24 #define min(a,b)  ((a) < (b) ? (a) : (b))
  25
  26 /* Check that field A (type AT) followed by field B (type BT) are
  27    packed according to P */
  28 #define test_pack(n, a, at, b, bt, p) \
  29         test(n, offsetof (struct SNAME, b) \
  30                 == min (offset (SNAME,a,at,__alignof__(bt)), \
  31                         offset (SNAME,a,at,p)))
  32
  33 /* Test offset of field F in structs s1 and s2 are the same.  */
  34 #define test_offset(n, s1, s2, f) \
  35         test (n, (offsetof(struct s1, f) == offsetof(struct s2, f)))
  36
  37 #define SNAME s0
  38 #include "pack-test-1.h"
  39
  40 #undef SNAME
  41 #define SNAME s1
  42 #pragma pack(push, p1, 1)
  43 #include "pack-test-1.h"
  44
  45 void SNAME() {
  46   test_pack(0, f0, char, f1, double, 1);
  47   test_pack(1, f2, short, f3, double, 1);
  48   test_pack(2, f4, int, f5, double, 1);
  49 }
  50
  51 #undef SNAME
  52 #define SNAME s2
  53 #pragma pack(push, p2, 2)
  54 #include "pack-test-1.h"
  55
  56 void SNAME() {
  57   test_pack(0, f0, char, f1, double, 2);
  58   test_pack(1, f2, short, f3, double, 2);
  59   test_pack(2, f4, int, f5, double, 2);
  60 }
  61
  62 #undef SNAME
  63 #define SNAME s3
  64 #pragma pack(push, p3, 4)
  65 #include "pack-test-1.h"
  66
  67 void SNAME() {
  68   test_pack(0, f0, char, f1, double, 4);
  69   test_pack(1, f2, short, f3, double, 4);
  70   test_pack(2, f4, int, f5, double, 4);
  71 }
  72
  73 #undef SNAME
  74 #define SNAME s4
  75 #pragma pack(pop)
  76 #include "pack-test-1.h"
  77
  78 void SNAME() {
  79   test_pack(0, f0, char, f1, double, 2);
  80   test_pack(1, f2, short, f3, double, 2);
  81   test_pack(2, f4, int, f5, double, 2);
  82 }
  83
  84 #undef SNAME
  85 #define SNAME s5
  86 #pragma pack(pop, p2)
  87 #include "pack-test-1.h"
  88
  89 void SNAME() {
  90   test_pack(0, f0, char, f1, double, 1);
  91   test_pack(1, f2, short, f3, double, 1);
  92   test_pack(2, f4, int, f5, double, 1);
  93 }
  94
  95 #undef SNAME
  96 #define SNAME s6
  97 #pragma pack(pop, p1)
  98 #include "pack-test-1.h"
  99
 100 void SNAME() {
 101   test_offset (0, s0, SNAME, f0);
 102   test_offset (1, s0, SNAME, f1);
 103   test_offset (2, s0, SNAME, f2);
 104   test_offset (3, s0, SNAME, f3);
 105   test_offset (4, s0, SNAME, f4);
 106   test_offset (5, s0, SNAME, f5);
 107 }
 108
 109 #undef SNAME
 110 #define SNAME s7
 111 #pragma pack(1)
 112 #include "pack-test-1.h"
 113
 114 void SNAME() {
 115   test_pack(0, f0, char, f1, double, 1);
 116   test_pack(1, f2, short, f3, double, 1);
 117   test_pack(2, f4, int, f5, double, 1);
 118 }
 119
 120 #undef SNAME
 121 #define SNAME s8
 122 #pragma pack(push, p2, 2)
 123 #include "pack-test-1.h"
 124
 125 void SNAME() {
 126   test_pack(0, f0, char, f1, double, 2);
 127   test_pack(1, f2, short, f3, double, 2);
 128   test_pack(2, f4, int, f5, double, 2);
 129 }
 130
 131 #undef SNAME
 132 #define SNAME s9
 133 #pragma pack(pop)
 134 #include "pack-test-1.h"
 135
 136 void SNAME() {
 137   test_pack(0, f0, char, f1, double, 1);
 138   test_pack(1, f2, short, f3, double, 1);
 139   test_pack(2, f4, int, f5, double, 1);
 140 }
 141
 142 #undef SNAME
 143 #define SNAME s10
 144 #pragma pack()
 145 #include "pack-test-1.h"
 146
 147 void SNAME() {
 148   test_offset (0, s0, SNAME, f0);
 149   test_offset (1, s0, SNAME, f1);
 150   test_offset (2, s0, SNAME, f2);
 151   test_offset (3, s0, SNAME, f3);
 152   test_offset (4, s0, SNAME, f4);
 153   test_offset (5, s0, SNAME, f5);
 154 }