gfortran -std=legacy hello.f -o hello.exe hello.exe Expected output: Hello, Fortran 77 on Windows 10 64-bit | Problem | Solution | |---------|----------| | gfortran not recognized | PATH not set → Add C:\mingw-w64\mingw64\bin | | unexpected end of file | File is not fixed-form → Save as .f , not .txt | | illegal statement in column 1 | Use -ffixed-form flag, or ensure 6 spaces before code | | missing libgfortran.dll | Compile with -static flag | 9. Conclusion No modern "Fortran 77-only" compiler exists for Windows 10 64-bit, nor is one needed. Both gfortran (MinGW-w64) and Intel oneAPI provide seamless, free, production-quality F77 support. For most users (students, researchers, engineers maintaining legacy code), gfortran via MinGW-w64 is the optimal choice due to its lightweight nature, no licensing, and excellent compatibility.
1. Executive Summary Finding: There is no active, standalone, modern "Fortran 77 only" compiler specifically marketed for Windows 10 64-bit. However, several free, modern Fortran compilers (which fully support the Fortran 77 standard) are readily available and recommended. fortran 77 compiler for windows 10 64-bit free download
✅ Free, viable, and fully functional – download MinGW-w64 + gfortran today. gfortran -std=legacy hello