I am compiling a system using the Intel C++ Compiler version 9.1 on a RedHat Linux ES 4.5 (kernel 2.6.9). When I use g++ to compile, I get nice 64-bit applications. When I use icc, I only get 32-bit applications. Is there a flag, setting, or something I am missing?
A typical compile line from the makefile looks like: icpc -o
The choice between 32- and 64-bit icpc is made by the PATH settings, as performed by the iccvars script, assuming that you have installed both compilers. For 9.1, this script was run like: source /cce/bin/iccvars.sh so the distinction was between /cce/ for 64-bit and /cc/ for 32-bit. 'which icpc' will show you whether you have /cce/ or /cc/ active. You would require the 64-bit g++ for library compatibility.