1 | #include <stdio.h>
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2 | #include <assert.h>
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3 | #include <stdlib.h>
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4 |
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5 | #define SHOW(x, fmt) printf( #x ": " fmt "\n", x )
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6 |
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7 | #ifdef ERRS
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8 | #define ERR(...) __VA_ARGS__
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9 | #else
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10 | #define ERR(...)
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11 | #endif
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12 |
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13 |
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14 |
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15 | int main() {
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16 |
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17 | /*
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18 | As in the last section, we inspect the declaration ...
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19 | */
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20 | float a[3][10];
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21 | /*
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22 |
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23 | */
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24 | static_assert(sizeof(float)==4); // floats (atomic elements) are 4 bytes
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25 | static_assert(sizeof(void*)==8); // pointers are 8 bytes
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26 | /*
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27 |
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28 | The significant axis of deriving expressions from @a@ is now ``itself,'' ``first element'' or ``first grand-element (meaning, first element of first element).''
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29 | */
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30 | static_assert(sizeof( a ) == 120); // the array, float[3][10]
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31 | static_assert(sizeof( a[0] ) == 40 ); // its first element, float[10]
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32 | static_assert(sizeof( a[0][0] ) == 4 ); // its first grand element, float
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33 |
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34 | static_assert(sizeof(&(a )) == 8 ); // pointer to the array, float(*)[3][10]
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35 | static_assert(sizeof(&(a[0] )) == 8 ); // pointer to its first element, float(*)[10]
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36 | static_assert(sizeof(&(a[0][0])) == 8 ); // pointer to its first grand-element, float*
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37 |
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38 | float (*pa )[3][10] = &(a );
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39 | float (*pa0 ) [10] = &(a[0] );
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40 | float *pa00 = &(a[0][0]);
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41 |
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42 | static_assert((void*)&a == (void*)&(a[0] ));
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43 | static_assert((void*)&a == (void*)&(a[0][0]));
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44 |
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45 | assert( (void *) pa == (void *) pa0 );
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46 | assert( (void *) pa == (void *) pa00 );
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47 |
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48 | // float (*b[3])[10];
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49 | float *b[3];
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50 | for (int i = 0; i < 3; i ++) {
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51 | b[i] = malloc(sizeof(float[10]));
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52 | }
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53 | a[2][3];
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54 | b[2][3];
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55 | /*
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56 |
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57 | */
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58 |
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59 | }
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