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Clarification required about bitfields


Hi,

Now LLVM and GCC essentially disagrees on simple test (minimized from
one of dejagnu tests):

#include <stdlib.h>

struct s {
  unsigned long long u33: 33;
  unsigned long long u40: 40;
  unsigned long long u41: 41;
};

struct s a = { 0x100000, 0x100000, 0x100000 };

int
main (void)
{
  if (a.u33 * a.u33 != 0)
    abort();

  exit (0);
}

Compiled on GCC 5.2 passes, compiled on Clang 3.7 aborts. But when I
filed bug https://llvm.org/bugs/show_bug.cgi?id=25852 against clang on
this, it was resolved as invalid with comment that GCC behaves
incorrect here.

How do you think: who is right and should I file this bug in gcc bugzilla now?

---
With best regards, Konstantin


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