This was asked for on IRC. Add something about the following: .f90, .f95, .f03 (and at some point .f08) and their captial version .F90, .F95, .F03 (and at some point .F08 for Fortran 2008) will default to free-format Fortran.
.for, .ftn and .f as well as .F, .FOR, .FTN and .FPP are considered as fixed form. The captial version is run through the C Preprocessor (cpp, sometimes also fpp called) prior compilation; .fpp is run though cpp even though lower cased. Present version: http://gcc.gnu.org/onlinedocs/gfortran/GNU-Fortran-and-GCC.html http://gcc.gnu.org/onlinedocs/gfortran/Preprocessing-and-conditional-compilation.html -- Summary: Document when fixed form and when free form source code is assumed Product: gcc Version: 4.3.0 Status: UNCONFIRMED Keywords: documentation Severity: enhancement Priority: P3 Component: fortran AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: burnus at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34175
