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icc 17.0.1 miscompiles valid C code at -O1 and above on x86_64-linux-gnu

Zhendong_Su
Beginner
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Compiler version and platform: 

Intel(R) C Intel(R) 64 Compiler for applications running on Intel(R) 64, Version 17.0.1.132 Build 20161005 

$ icc -O0 small.c; ./a.out; echo $?
1
$ 
$ icc -O1 small.c; ./a.out; echo $?
0
$ 
$ cat small.c
struct
{
  int f:2;
} volatile a = { -1 };

int b = 1;

int main ()
{
  short c = 0;
  if (!(!b || a.f > 0))
    c = 1;
  return c;
}
$ 

 

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