fix (potential) floating point exceptions
fix (potential) floating point exceptions

When reading HLT clusters during TPC reconstruction, some clusters end up
with non-sense values rendering them unusable, and, worst-case, lead to a
FPE. This is assumingly caused by a gcc bug when inlining
AliHLTTPCHWClusterMerger::iterator::operator*()
and hence affects all merged clusters. This can be prevented by forcing gcc
not to inline (e.g. attribute noinline), by using clang, or by this very patch.

sebaleh/AliRoot,alisw/AliRoot,jgrosseo/AliRoot,jgrosseo/AliRoot,coppedis/AliRoot,alisw/AliRoot,ecalvovi/AliRoot,miranov25/AliRoot,ALICEHLT/AliRoot,coppedis/AliRoot,sebaleh/AliRoot,mkrzewic/AliRoot,ALICEHLT/AliRoot,shahor02/AliRoot,miranov25/AliRoot,alisw/AliRoot,jgrosseo/AliRoot,alisw/AliRoot,ecalvovi/AliRoot,ecalvovi/AliRoot,ecalvovi/AliRoot,shahor02/AliRoot,mkrzewic/AliRoot,ecalvovi/AliRoot,miranov25/AliRoot,coppedis/AliRoot,shahor02/AliRoot,jgrosseo/AliRoot,ALICEHLT/AliRoot,ecalvovi/AliRoot,alisw/AliRoot,alisw/AliRoot,coppedis/AliRoot,ALICEHLT/AliRoot,sebaleh/AliRoot,shahor02/AliRoot,miranov25/AliRoot,sebaleh/AliRoot,alisw/AliRoot,jgrosseo/AliRoot,jgrosseo/AliRoot,sebaleh/AliRoot,miranov25/AliRoot,mkrzewic/AliRoot,shahor02/AliRoot,sebaleh/AliRoot,miranov25/AliRoot,coppedis/AliRoot,coppedis/AliRoot,miranov25/AliRoot,mkrzewic/AliRoot,sebaleh/AliRoot,mkrzewic/AliRoot,alisw/AliRoot,ALICEHLT/AliRoot,ALICEHLT/AliRoot,mkrzewic/AliRoot,ALICEHLT/AliRoot,miranov25/AliRoot,jgrosseo/AliRoot,coppedis/AliRoot,shahor02/AliRoot,shahor02/AliRoot,coppedis/AliRoot,mkrzewic/AliRoot,ecalvovi/AliRoot