Error migrating from Win32 to x64

[CarlosR]

The code is written in FORTRAN and dates back to the 1990s. I migrated the project to Visual Studio 2022 and installed the 2025.3 compiler, but it only supports x64. Although the code compiles successfully, the software does not behave correctly: it branches into incorrect options and enters IF statements that should not apply.

When compiled as Win32, the program works correctly. The issue appears only in x64, but I don’t know how to fix it. The program has been running in Win32 for more than 30 years. Alternatively, is there a way to get a FORTRAN compiler that still supports Win32?

[DavidWhite]

You need to share some code with us, so that we can explore what is happening.

There are no Win32 Intel compilers available now.

[witwald]

@CarlosR, in case it's of any use, take a look at the details provided at the following link:

This Is The Last Planned Version of The Intel® Fortran Compiler Classic (ifort), as The Intel® Fortran Compiler (ifx) Becomes our Primary Compiler 

[GVautier]

The problem is probably due to the change in the size of default integer and pointers if any.

[Steve_Lionel]

The size of default integer did not change, but the size of pointers did.

[andrew_4619]

Caution! Are you saying it enters IF branches based on using the debugger? Because the current IFX debugger does some strange and misleading jumping around which you will find discussed in other threads. I most cases the code is actually running fine it is just the instructions in the code are not quite tagged in sync with the best line in the source.

As others have said 32/64 bit integer pointers  is particularly a problem if you use windows sdk/library functions that use 'handles'.