EIGEN_ALLOCA is only defined on Linux and Windows with MSVC

Submitted by Christoph Hertzberg @chhtz

Assigned to Nobody

Link to original bugzilla bug (#729)
Version: 3.2

Description

Checking the definition of EIGEN_ALLOCA in src/Core/util/Memory.h it appears that there is a default implementation only for Linux and Windows with MSVC. That excludes at least MacOS and Windows with MinGW/Cygwin (which all support alloca).

Blocking

#558 (closed)