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@niklas-ourmachinery
Created April 8, 2019 16:42
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Comma operator initialization bug in MSVC compiler
#include <inttypes.h>
#include <stdio.h>
typedef struct
{
uint64_t a;
uint64_t b;
} s_t;
s_t s = {
0x7bd9d3ae0409903aULL,
(0, 0x7bd9d3ae0409903aULL),
};
int main(int argc, char **argv)
{
s_t t = {
0x7bd9d3ae0409903aULL,
(0, 0x7bd9d3ae0409903aULL),
};
printf("s.a = %" PRIx64 "\n", s.a);
printf("s.b = %" PRIx64 "\n", s.b);
printf("t.a = %" PRIx64 "\n", t.a);
printf("t.b = %" PRIx64 "\n", t.b);
}
/*
When compiled as .c this produces the output:
s.a = 7bd9d3ae0409903a
s.b = 409903a
t.a = 7bd9d3ae0409903a
t.b = 7bd9d3ae0409903a
When compiled as .cpp this produces the expected output:
s.a = 7bd9d3ae0409903a
s.b = 7bd9d3ae0409903a
t.a = 7bd9d3ae0409903a
t.b = 7bd9d3ae0409903a
*/
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