warning: dereferencing type-punned pointer will break strict-aliasing rules

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warning: dereferencing type-punned pointer will...
\ Jeffrey Holle (24 Jul 2007)
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. . \ Jeffrey Holle (25 Jul 2007)
. . \ Nathan Sidwell (26 Jul 2007)

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Subject:	warning: dereferencing type-punned pointer will break strict-aliasing rules
Group:	Gcc-help
From:	Jeffrey Holle
Date:	24 Jul 2007

I am using gcc version 4.1.2.

I am writing a Boost.Build based system to build wxWidgets using
applications.

This build system has default build variants "debug" and "release".

On release builds, wxWidgets code emits a lot of these warnings:
warning: dereferencing type-punned pointer will break strict-aliasing
rules

Questions:

1. Are these warnings benign? If so can they be suppressed?
2. If not, what level of optimization should I regress to avoid these
warnings?