[easybuild] 2015b toolchains : non-GCC- and GCC-versions

[Backeljauw Franky]

Hello,

So now I’ve installed both foss-2015b.eb and intel-2015b.eb, which gives me 
this list of modules:

Autoconf/2.69-GNU-4.9.3-2.25                             foss/2015b             
                                  intel/2015b
Automake/1.15-GNU-4.9.3-2.25                             
GCC/4.9.3-binutils-2.25                                  
libtool/2.4.6-GNU-4.9.3-2.25
Autotools/20150215-GNU-4.9.3-2.25                        GNU/4.9.3-2.25         
                                  M4/1.4.17
binutils/2.25                                            gompi/2015b            
                                  M4/1.4.17-GCC-4.9.3-binutils-2.25
binutils/2.25-GCC-4.9.3-binutils-2.25                    
hwloc/1.11.0-GNU-4.9.3-2.25                              
M4/1.4.17-GNU-4.9.3-2.25
Bison/3.0.4                                              
icc/2015.3.187-GNU-4.9.3-2.25                            
numactl/2.0.10-GNU-4.9.3-2.25
Bison/3.0.4-GCC-4.9.3-binutils-2.25                      
iccifort/2015.3.187-GNU-4.9.3-2.25                       
OpenBLAS/0.2.14-GNU-4.9.3-2.25-LAPACK-3.5.0
EasyBuild/2.2.0                                          
ifort/2015.3.187-GNU-4.9.3-2.25                          
OpenMPI/1.8.8-GNU-4.9.3-2.25
FFTW/3.3.4-gompi-2015b                                   
iimpi/7.3.5-GNU-4.9.3-2.25                               
ScaLAPACK/2.0.2-gompi-2015b-OpenBLAS-0.2.14-LAPACK-3.5.0
flex/2.5.39                                              
imkl/11.2.3.187-iimpi-7.3.5-GNU-4.9.3-2.25               zlib/1.2.8
flex/2.5.39-GCC-4.9.3-binutils-2.25                      
impi/5.0.3.048-iccifort-2015.3.187-GNU-4.9.3-2.25        
zlib/1.2.8-GCC-4.9.3-binutils-2.25

I’m wondering: why do I have both binutils/2.25 and 
binutils/2.25-GCC-4.9.3-binutils-2.25 (the same for Bison, flex, M4, zlib)?
Are the non-GCC-versions actually used, or are they just dependencies needed to 
built the GCC-versions?

— Regards,

Franky