OpenEXR_CTL Clang warnings

[nemysis]

Please make cleaner Code that works good with Clang.

From FreeBSD 10 is default used Clang for Ports.

I have these build messages

...
libtool: compile:  clang++ -DPACKAGE_NAME=\"CTL\" -DPACKAGE_TARNAME=\"ctl\" -DPACKAGE_VERSION=\"1.4.1\" "-DPACKAGE_STRING=\"CTL 1.4.1\"" -DPACKAGE_BUGREPORT=\$
\" -DPACKAGE_URL=\"\" -DPACKAGE=\"ctl\" -DVERSION=\"1.4.1\" -DSTDC_HEADERS=1 -DHAVE_SYS_TYPES_H=1 -DHAVE_SYS_STAT_H=1 -DHAVE_STDLIB_H=1 -DHAVE_STRING_H=1 -DHA$
E_MEMORY_H=1 -DHAVE_STRINGS_H=1 -DHAVE_INTTYPES_H=1 -DHAVE_STDINT_H=1 -DHAVE_UNISTD_H=1 -DHAVE_DLFCN_H=1 -DLT_OBJDIR=\".libs/\" -DSTDC_HEADERS=1 -DHAVE_LIMITS$
H=1 -DHAVE_UNISTD_H=1 -DHAVE_COMPLETE_IOMANIP=1 -I. -D_THREAD_SAFE -I/usr/local/include/OpenEXR -I.. -pipe -O2 -pipe -fno-strict-aliasing -MT CtlLookupTable.l$
 -MD -MP -MF .deps/CtlLookupTable.Tpo -c CtlLookupTable.cpp -o CtlLookupTable.o >/dev/null 2>&1
In file included from CtlRbfInterpolator.cpp:56:
./CtlSparseMatrix.h:212:10: warning: comparison of unsigned expression < 0 is always false [-Wtautological-compare]
        if (*ri < 0)
            ~~~ ^ ~
./CtlSparseMatrix.h:216:13: warning: comparison of unsigned expression < 0 is always false [-Wtautological-compare]
        while (*ce < 0 && ce <= re)
               ~~~ ^ ~
./CtlSparseMatrix.h:245:10: warning: comparison of unsigned expression < 0 is always false [-Wtautological-compare]
        if (*ri < 0)
            ~~~ ^ ~
./CtlSparseMatrix.h:249:13: warning: comparison of unsigned expression < 0 is always false [-Wtautological-compare]
        while (*ce < 0 && ce <= re)
               ~~~ ^ ~
./CtlSparseMatrix.h:245:10: warning: comparison of unsigned expression < 0 is always false [-Wtautological-compare]
        if (*ri < 0)
            ~~~ ^ ~
libtool: compile:  clang++ -DPACKAGE_NAME=\"CTL\" -DPACKAGE_TARNAME=\"ctl\" -DPACKAGE_VERSION=\"1.4.1\" "-DPACKAGE_STRING=\"CTL 1.4.1\"" -DPACKAGE_BUGREPORT=\$
\" -DPACKAGE_URL=\"\" -DPACKAGE=\"ctl\" -DVERSION=\"1.4.1\" -DSTDC_HEADERS=1 -DHAVE_SYS_TYPES_H=1 -DHAVE_SYS_STAT_H=1 -DHAVE_STDLIB_H=1 -DHAVE_STRING_H=1 -DHA$
E_MEMORY_H=1 -DHAVE_STRINGS_H=1 -DHAVE_INTTYPES_H=1 -DHAVE_STDINT_H=1 -DHAVE_UNISTD_H=1 -DHAVE_DLFCN_H=1 -DLT_OBJDIR=\".libs/\" -DSTDC_HEADERS=1 -DHAVE_LIMITS$
H=1 -DHAVE_UNISTD_H=1 -DHAVE_COMPLETE_IOMANIP=1 -I. -D_THREAD_SAFE -I/usr/local/include/OpenEXR -I.. -pipe -O2 -pipe -fno-strict-aliasing -MT CtlColorSpace.lo 
-MD -MP -MF .deps/CtlColorSpace.Tpo -c CtlColorSpace.cpp -o CtlColorSpace.o >/dev/null 2>&1
./CtlLinearSolver.h:576:12: note: in instantiation of function template specialization 'Ctl::CRSOperator<double>::applyT<__gnu_cxx::__normal_iterator<double *,
 std::vector<double, std::allocator<double> > >, __gnu_cxx::__normal_iterator<double *, std::vector<double, std::allocator<double> > > >' requested here
    op().A.applyT(b_first, b_last, c_first, c_last);
           ^
./CtlLinearSolver.h:310:2: note: in instantiation of function template specialization 'Ctl::LSS<double, Ctl::CRSOperator<double>, Ctl::CG<double, Ctl::LSSOper$
tor<double, Ctl::CRSOperator<double> >, Ctl::NullLinearOperator>, Ctl::NullLinearOperator>::constants<__gnu_cxx::__normal_iterator<double *, std::vector<doubl$
, std::allocator<double> > >, __gnu_cxx::__normal_iterator<double *, std::vector<double, std::allocator<double> > > >' requested here
        constants(b_first, b_last, c.begin(), c.end());
        ^
CtlRbfInterpolator.cpp:190:14: note: in instantiation of function template specialization 'Ctl::LSS<double, Ctl::CRSOperator<double>, Ctl::CG<double, Ctl::LSS$
perator<double, Ctl::CRSOperator<double> >, Ctl::NullLinearOperator>, Ctl::NullLinearOperator>::operator()<__gnu_cxx::__normal_iterator<double *, std::vector<$
ouble, std::allocator<double> > >, __gnu_cxx::__normal_iterator<double *, std::vector<double, std::allocator<double> > > >' requested here
    lssAffine(b.begin(), b.end(), _affine.begin(), _affine.end());
             ^
In file included from CtlRbfInterpolator.cpp:56:
./CtlSparseMatrix.h:249:13: warning: comparison of unsigned expression < 0 is always false [-Wtautological-compare]
        while (*ce < 0 && ce <= re)
               ~~~ ^ ~
./CtlSparseMatrix.h:212:10: warning: comparison of unsigned expression < 0 is always false [-Wtautological-compare]
        if (*ri < 0)
            ~~~ ^ ~
./CtlLinearSolver.h:241:4: note: in instantiation of function template specialization 'Ctl::CRSOperator<double>::apply<__gnu_cxx::__normal_iterator<double *, $
td::vector<double, std::allocator<double> > >, __gnu_cxx::__normal_iterator<double *, std::vector<double, std::allocator<double> > > >' requested here
        A.apply(x_first, x_last, aux.begin(), aux.end());
          ^
./CtlLinearSolver.h:404:7: note: in instantiation of function template specialization 'Ctl::LSSOperator<double, Ctl::CRSOperator<double> >::apply<__gnu_cxx::_$
normal_iterator<double *, std::vector<double, std::allocator<double> > >, __gnu_cxx::__normal_iterator<double *, std::vector<double, std::allocator<double> > $
 >' requested here
    A.apply(x_first, x_last, t.begin(), t.end()); // t = A * x
      ^
./CtlLinearSolver.h:388:9: note: in instantiation of function template specialization 'Ctl::CG<double, Ctl::LSSOperator<double, Ctl::CRSOperator<double> >, Ct$
::NullLinearOperator>::cg<__gnu_cxx::__normal_iterator<double *, std::vector<double, std::allocator<double> > >, __gnu_cxx::__normal_iterator<double *, std::v$
ctor<double, std::allocator<double> > > >' requested here
        return cg(b_first, b_last, x_first, x_last);
               ^
./CtlLinearSolver.h:311:9: note: in instantiation of function template specialization 'Ctl::CG<double, Ctl::LSSOperator<double, Ctl::CRSOperator<double> >, Ct$
::NullLinearOperator>::operator()<__gnu_cxx::__normal_iterator<double *, std::vector<double, std::allocator<double> > >, __gnu_cxx::__normal_iterator<double *$
 std::vector<double, std::allocator<double> > > >' requested here
        return solver(c.begin(), c.end(), x_first, x_last);
               ^
CtlRbfInterpolator.cpp:190:14: note: in instantiation of function template specialization 'Ctl::LSS<double, Ctl::CRSOperator<double>, Ctl::CG<double, Ctl::LSS$
perator<double, Ctl::CRSOperator<double> >, Ctl::NullLinearOperator>, Ctl::NullLinearOperator>::operator()<__gnu_cxx::__normal_iterator<double *, std::vector<$
ouble, std::allocator<double> > >, __gnu_cxx::__normal_iterator<double *, std::vector<double, std::allocator<double> > > >' requested here
    lssAffine(b.begin(), b.end(), _affine.begin(), _affine.end());
             ^
In file included from CtlRbfInterpolator.cpp:56:
./CtlSparseMatrix.h:216:13: warning: comparison of unsigned expression < 0 is always false [-Wtautological-compare]
        while (*ce < 0 && ce <= re)
               ~~~ ^ ~
mv -f .deps/CtlLookupTable.Tpo .deps/CtlLookupTable.Plo
mv -f .deps/CtlColorSpace.Tpo .deps/CtlColorSpace.Plo
8 warnings generated.
libtool: compile:  clang++ -DPACKAGE_NAME=\"CTL\" -DPACKAGE_TARNAME=\"ctl\" -DPACKAGE_VERSION=\"1.4.1\" "-DPACKAGE_STRING=\"CTL 1.4.1\"" -DPACKAGE_BUGREPORT=\"
\" -DPACKAGE_URL=\"\" -DPACKAGE=\"ctl\" -DVERSION=\"1.4.1\" -DSTDC_HEADERS=1 -DHAVE_SYS_TYPES_H=1 -DHAVE_SYS_STAT_H=1 -DHAVE_STDLIB_H=1 -DHAVE_STRING_H=1 -DHAV
E_MEMORY_H=1 -DHAVE_STRINGS_H=1 -DHAVE_INTTYPES_H=1 -DHAVE_STDINT_H=1 -DHAVE_UNISTD_H=1 -DHAVE_DLFCN_H=1 -DLT_OBJDIR=\".libs/\" -DSTDC_HEADERS=1 -DHAVE_LIMITS_
H=1 -DHAVE_UNISTD_H=1 -DHAVE_COMPLETE_IOMANIP=1 -I. -D_THREAD_SAFE -I/usr/local/include/OpenEXR -I.. -pipe -O2 -pipe -fno-strict-aliasing -MT CtlRbfInterpolato
r.lo -MD -MP -MF .deps/CtlRbfInterpolator.Tpo -c CtlRbfInterpolator.cpp -o CtlRbfInterpolator.o >/dev/null 2>&1
mv -f .deps/CtlRbfInterpolator.Tpo .deps/CtlRbfInterpolator.Plo
...