g++ 4.3.1 implements std::norm(x) as std::abs(x) squared for built-in floating
point types. I believe this is taking the standard too literally. It says
std::norm should return "magnitude of x squared" in the mathematical sense
(i.e. a floating-point approximation thereof), which is not necessarily
equivalent to "the result of std::abs(x) squared". I think the intent of
std::norm was clearly to avoid doing a square root if the magnitude is to be
squared immediatelly.
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Summary: unnecessarily strict std::norm implementation
Product: gcc
Version: 4.3.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: highegg at gmail dot com
GCC host triplet: x86_64-suse-linux
GCC target triplet: x86_64-suse-linux
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39340
