[PD-dev] [ pure-data-Patches-3458347 ] spec2_sqrt~.c won't work in double precision, violates C99

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Patches item #3458347, was opened at 2011-12-12 11:43
Message generated for change (Comment added) made by eighthave
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>Category: externals
Group: None
Status: Open
Resolution: None
Priority: 5
Private: No
Submitted By: Hans-Christoph Steiner (eighthave)
Assigned to: musil (tmusil)
Summary: spec2_sqrt~.c won't work in double precision, violates C99

Initial Comment:
spec2_sqrt~.c includes type punning, which violates the C99 standard, breaks when t_float/t_sample are 64-bit doubles, and also breaks modern compiler optimizations.  Here's the compiler warning:

pd-extended/externals/iem/iem_spec2/src/spec2_sqrt~.c:28: warning: dereferencing type-punned pointer will break strict-aliasing rules


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>Comment By: Hans-Christoph Steiner (eighthave)
Date: 2012-12-20 16:29

Message:
I attached a patch that uses the standard C99-compliant technique for doing
this kind of type-punning.  It uses a union.

http://stackoverflow.com/questions/11442708/type-punning-and-unions-in-c

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