Compiling qhull

Dear all,

I'm trying to compiler qhull http://www.qhull.org/. I edited the makefile

by specifying CC = icc and CXX = icpc, I've thought it was enough.

However the compilation fails. There are an additional options for CC/CXX

CC_OPTS1  = -O2 -fPIC -ansi -Isrc/libqhull $(CC_WARNINGS)
CXX_OPTS1 = -O2 -Dqh_QHpointer -Isrc/ -Isrc/libqhullcpp -Isrc/libqhull $(CXX_WARNINGS)

the warning switches are

CC_WARNINGS  = -Wall -Wcast-qual -Wextra -Wwrite-strings -Wshadow
CXX_WARNINGS = -Wall -Wcast-qual -Wextra -Wwrite-strings -Wno-sign-conversion -Wshadow -Wconversion

The (main) error occurs at line (106) of qhull-2012.1/src/libqhull/qhull_a.h, i.e. at

#if defined(__INTEL_COMPILER) && !defined(QHULL_OS_WIN)
template <typename T>
inline void qhullUnused(T &x) { (void)x; }
#  define QHULL_UNUSED(x) qhullUnused(x);
#else
#  define QHULL_UNUSED(x) (void)x;
#endif

I cannot figure what is the solution. Can anyone help me?

Thank you, very much.

Fabio