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Re: Bogus testcase?

From: Paolo Bonzini <paolo dot bonzini at lu dot unisi dot ch>
To: GCC Development <gcc at gcc dot gnu dot org>, law at redhat dot com
Date: Tue, 15 Nov 2005 22:29:18 +0100
Subject: Re: Bogus testcase?
References: <1132089344.484.56.camel@slowpoke>

for (i = ((unsigned) ~0 >> 1) - 3; i <= ((unsigned) ~0 >> 1) + 3; i++)

i <= ((unsigned)~0>>1) + 3
Seems like it overflows to me, or would cause "i" to have to
overflow to terminate the loop.

Yes, the two expression are respectively 0x7FFFFFFC and 0x80000002.

It ought to work with -fwrapv, though.

Paolo

References:
- Bogus testcase?
  - From: Jeffrey A Law

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