Hello all, This is my first post here. I just need a help to explain why I can access (both read and write) private module variable x in this program? is it a bug or I understood the private clause incorrectly? imronuke@imronuke-p02:$ cat test.f90 module foo1 private real :: x = 1 …

You need to add ‘implicit none’ in each module and in your main program. Without you, are implicitly declaring a variable called ‘x’ in your main program, which is difference from the one in the module.

You need to add ‘implicit none’ in each module and in your main program. Without you, are implicitly declaring a variable called ‘x’ in your main program, which is difference from the one in the module. OMG, how come I forgot this basic thing. Thank you.

Continuing the discussion from Why I can access private module variable in this program? : Implicit typing strikes again. Yes, yes. IMHO, this is should have been enabled by default in modern Fortran compilers unless stated otherwise. I know there has been a long debate on this in the Fotran Comm…

[image] imronuke: IMHO, this is should have been enabled by default in modern Fortran compilers @imronuke , Welcome to the discourse! Fortran compilers, barring LFortran, do not appear at all keen to enable explicit typing by default. For them, there are always these unnamed but “bigger” an…

One “bigger” and “more important” customer was the US Department of Defense. They introduced implicit none in MIL-STD-1753 in 1978 as an extension to f77. That forced vendors to implement it (and various other features that seem much less contentious) if they wanted DoD to buy their compilers.

[image] FortranFan: So look into -fimplicit-none option if you are using gfortran. This is to give a balanced perspective of this approach. If you use the compiler option to “fix” the code, then you must use that option every time you compile your code from now to infinity. And everyone else …

[image] RonShepard: This is to give a balanced perspective of this approach … Readers can appreciate OP understands the need to include implicit none in each relevant scope but inadvertently missed out on doing so. OP shows 3 such scopes in the original post itself, but may have many more in…

[image] FortranFan: OP can then proceed to use the compiler error messages to guide with the introduction of implicit none in the scopes as well as explicitly declare the types of the objects in question. I agree with this. If compiler options help the programmer fix the code, then I think th…

[image] imronuke: program test use foo2 x = 5 write(*,*) x, y end program Wouldn’t it be useful if a programmer could, at any point in the program, print out the names and the sources of all variables that are in scope? If that were done here, then the programmer could have eas…

Why I can access private module variable in this program?

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jacobwilliams January 27, 2023, 2:01am 4

Implicit typing strikes again.

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Why I can access private module variable in this program?

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