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Date:	Mon, 13 Nov 2023 15:38:32 +0100
To:	Bruno Haible <bruno AT clisp DOT org>
Subject:	Re: rand is not ISO C compliant in Cygwin
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From:	Corinna Vinschen via Cygwin <cygwin AT cygwin DOT com>
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On Nov 13 15:25, Bruno Haible wrote:
> Corinna Vinschen wrote:
> > The rand() function would still not use locking but AFAICS that's
> > not actually required by POSIX or ISO C.
> 
> Correct. Those who want an MT-safe rand-like function need to use random(),
> not rand().

FTR, we have to differ here between plain newlib targets and Cygwin.

While Cygwin comes with it's own, table-based random() implementation
taken from BSD back in 2007, newlib's random is basically equivalent to
rand() for the sake of bare-metal and other targets with high memory
pressure.  We shouldn't change the latter since multi-threading
compliance is usually not much of a problem for that target audience.


Corinna


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