When compiling Geant4 10.04 on a 32 bit SL5 environment with custom-built GCC 6.3.0 I get these errors: $ cd /wizard/02/software/source/geant4.10.04.build/source/externals/clhep && /wizard/02/software/install/GCC_6.3.0/bin/c++ -DCLHEP_EXPORT -DG4VERBOSE -DG4_STORE_TRAJECTORY -DG4clhep_EXPORTS -DGEANT4_DEVELOPER_Release -I/wizard/02/software/source/geant4.10.04/source/externals/clhep/include -W -Wall -pedantic -Wno-non-virtual-dtor -Wno-long-long -Wwrite-strings -Wpointer-arith -Woverloaded-virtual -Wno-variadic-macros -Wshadow -pipe -DG4USE_STD11 -O3 -DNDEBUG -fno-trapping-math -ftree-vectorize -fno-math-errno -fPIC -std=c++11 -o CMakeFiles/G4clhep.dir/src/MixMaxRng.cc.o -c /wizard/02/software/source/geant4.10.04/source/externals/clhep/src/MixMaxRng.cc /wizard/02/software/source/geant4.10.04/source/externals/clhep/src/MixMaxRng.cc: Assembler messages: /wizard/02/software/source/geant4.10.04/source/externals/clhep/src/MixMaxRng.cc:717: Error: suffix or operands invalid for `add' /wizard/02/software/source/geant4.10.04/source/externals/clhep/src/MixMaxRng.cc:717: Error: suffix or operands invalid for `btr' /wizard/02/software/source/geant4.10.04/source/externals/clhep/src/MixMaxRng.cc:717: Error: suffix or operands invalid for `adc'
SL5 is a system no longer supported since long. Please, read the release notes for the the systems supported by recent Geant4 releases.