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Subject: Re: Pure/const function not getting executed as the first operand
 to logical OR ( || ) (C++)
From: Xi Ruoyao <xry111@mengyan1223.wang>
To: Vishal Subramanyam <vishalsubramanyam@outlook.com>
Cc: gcc-help@gcc.gnu.org
Date: Sun, 23 Jan 2022 18:02:46 +0800
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On Sun, 2022-01-23 at 09:56 +0000, Vishal Subramanyam wrote:
> This still doesn't explain why an O1 level optimization can violate
> the standard by not evaluating the first operand.

It's not violating the standard.  The standard says division-by-zero is
an undefined behavior, so the compiler can do anything.

> What optimization is my code triggering with -fno-inline? My function
> clearly has a return value, so how did the compiler
> decide that the return value doesn't matter?

-- 
Xi Ruoyao <xry111@mengyan1223.wang>
School of Aerospace Science and Technology, Xidian University