http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47175
Summary: no predefined macros __amd64, __amd64__, __x86_64 __x86_64__ in prepocessor Product: gcc Version: 4.4.5 Status: UNCONFIRMED Severity: normal Priority: P3 Component: fortran AssignedTo: unassig...@gcc.gnu.org ReportedBy: jan.raub...@gmx.de Matlab and probably other software uses the predefined macros to check for the current platform to enable long pointer or not. I have found that the macros above are no more in gfortran 4.4 and higher. The only way to check for the right platform is the __LP64__ macro which seems not to be used on other compiles like sunf90. It takes me some hours to find why a Matlab mex file crashes immediately after calling. Whith gcc these macros are available, why not whith gfortran? Jan