Messages in this thread | | | Date | Wed, 25 Apr 2012 15:54:31 +0400 | From | Konstantin Khlebnikov <> | Subject | Re: [PATCH 1/4] compiler.h: introduce unused_expression() macro |
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Cong Wang wrote: > On 04/25/2012 07:26 PM, Konstantin Khlebnikov wrote: >> Sometimes we want to check some expressions correctness in compile-time without >> generating extra code. "(void)(e)" does not work if expression has side-effects. >> This patch introduces macro unused_expression() which helps in this situation. >> > > Interesting, I am wondering why gcc doesn't eliminate the code as we > pass either -O2 or -Os to it.
It cannot do this if expression has some side-effects, for example if it contains BUG().
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