[eigen] PacketMath.h compiler error, GCC4.9 on Ubuntu 15.04

[Mark Sauder <mcsauder@xxxxxxxxx>]

Hi Everyone,

I was curious if anyone else was seeing compiler errors like the following in the past few days: 

/usr/include/eigen3/Eigen/src/Core/arch/SSE/PacketMath.h:584:42: error: cannot convert ‘Eigen::internal::unpacket_traits<__vector(2) long long int>::type {aka __vector(2) long long int}’ to ‘int’ in return

   return pfirst(_mm_hadd_epi32(tmp0,tmp0));

/usr/include/eigen3/Eigen/src/Core/arch/SSE/PacketMath.h: In function ‘typename Eigen::internal::unpacket_traits<T>::type Eigen::internal::predux(const Packet&) [with Packet = Eigen::internal::eigen_packet_wrapper<__vector(2) long long int>; typename Eigen::internal::unpacket_traits<T>::type = int]’:

/usr/include/eigen3/Eigen/src/Core/arch/SSE/PacketMath.h:584:42: error: cannot convert ‘Eigen::internal::unpacket_traits<__vector(2) long long int>::type {aka __vector(2) long long int}’ to ‘int’ in return

   return pfirst(_mm_hadd_epi32(tmp0,tmp0));

/usr/include/eigen3/Eigen/src/Core/arch/SSE/PacketMath.h:584:42:   required from here

/usr/include/eigen3/Eigen/src/Core/GenericPacketMath.h:299:13: error: ‘typename Eigen::internal::unpacket_traits<T>::type Eigen::internal::pfirst(const Packet&) [with Packet = __vector(2) long long int; typename Eigen::internal::unpacket_traits<T>::type = __vector(2) long long int]’ conflicts with a previous declaration

 { return a; }

It looks like it might track from this commit but I need to do a little more testing to nail that down with certainty.

Anyway, just wanted to ask if anyone was having that same trouble.

Thanks for all of the work that is going on in Eigen right now, it certainly is an amazing library. (Long live Eigen! :) )

Respectfully,

Mark

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Sauder