Created
May 11, 2020 19:30
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Experiment with union/struct field access generation
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// Experiment with expressions for reading from structs and union fields. | |
// https://godbolt.org/z/G_fsbD | |
typedef union { | |
struct { | |
long u; | |
short v; | |
char w; | |
} t1; | |
struct { | |
int a[2]; | |
char *p; | |
} t2; | |
} u_type; | |
#define CONCAT_IMPL(x, y) x##y | |
#define CONCAT(x, y) CONCAT_IMPL(x, y) | |
#define GET(Dest, expr) void CONCAT(get, __COUNTER__)(u_type *up, Dest *dest) { *dest = expr;} | |
GET(long, up->t1.u) | |
GET(short, up->t1.v) | |
GET(char*, &up->t1.w) | |
GET(int*, up->t2.a) | |
GET(int, up->t2.a[up->t1.u]) | |
GET(char, *up->t2.p) |
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