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Re: changing "configure" to default to "gcc -g -O2 -fwrapv ..."

From: Robert Dewar <dewar at adacore dot com>
To: Richard Kenner <kenner at vlsi1 dot ultra dot nyu dot edu>
Cc: dewar at gnat dot com, autoconf-patches at gnu dot org, bug-gnulib at gnu dot org, eggert at cs dot ucla dot edu, gcc at gcc dot gnu dot org, gdr at integrable-solutions dot net
Date: Sat, 30 Dec 2006 22:12:07 -0500
Subject: Re: changing "configure" to default to "gcc -g -O2 -fwrapv ..."
References: <20061231010207.C200A48CC4B@nile.gnat.com> <10612310154.AA00174@vlsi1.ultra.nyu.edu>

Richard Kenner wrote:

I found my copy of K&R (Second Edition).  Page 200: "The handling of overflow,
divide check, and other exceptions in expression evaluation is not defined
by the language.  Most existing implementations of C ignore overflow in
evaluation of signed integral expressions and assignments, but this behavior
is not guaranteed."

OK, that's what I remembered, so in fact the new C standard has changed nothing from a definitional point of view, it is just that people got in the habit of ignoring the definition and going with what the compiler(s) happened to do.

References:
- Re: changing "configure" to default to "gcc -g -O2 -fwrapv ..."
  - From: Robert Dewar
- Re: changing "configure" to default to "gcc -g -O2 -fwrapv ..."
  - From: Richard Kenner

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