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Re: std::max: if versus ?:

From: Paolo Carlini <paolo dot carlini at oracle dot com>
To: libstdc++ at gcc dot gnu dot org
Cc: Marc Glisse <marc dot glisse at inria dot fr>
Date: Thu, 20 Sep 2012 14:06:51 +0200
Subject: Re: std::max: if versus ?:
References: <alpine.DEB.2.02.1209201338430.7104@stedding.saclay.inria.fr>

On 09/20/2012 01:55 PM, Marc Glisse wrote:

Hello,

I noticed that std::max is implemented as:
      //return  __a < __b ? __b : __a;
      if (__a < __b)
        return __b;
      return __a;
Notice how it doesn't use the ?: code but the "if" version instead. Looking at the history, this seems to come from SGI. Does someone know why it was done this way?

I'm going to tell you something very vague and non technical, but in the past, outside std::max, I had quite often to use the above instead of a conditional operator as a second thought, when (maybe on a less common target) a test "unexpectedly" failed with a conversion error. Does that help you figuring out the technical details of the issue?

Paolo.

Follow-Ups:
- Re: std::max: if versus ?:
  - From: Paolo Carlini
- Re: std::max: if versus ?:
  - From: Marc Glisse

References:
- std::max: if versus ?:
  - From: Marc Glisse

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