topic Re: format syntax error in Intel® Fortran Compiler

format syntax error

Luis2 — Sat, 21 Mar 2009 16:27:04 GMT

Hi

By default the debugger does not detect the format error

print a ! instead print *,a

I have inspected the project properties and can not find how to change this

Re: format syntax error

Peter — Sat, 21 Mar 2009 22:03:53 GMT

Quoting - Luis

Hi

By default the debugger does not detect the format error

print a ! instead print *,a

I have inspected the project properties and can not find how to change this

Luis,

What compiler are you using???

Re: format syntax error

lklawrie — Sun, 22 Mar 2009 15:07:43 GMT

I think it will be hard for the compiler (any compiler) to detect your intentions here as the print statement has changed with standards:

print a

suggests using a as the format -- no longer do formats have to be numbers and format statements. With some compiler settings, you would probably get an error at runtime.

Linda

Re: format syntax error

Luis2 — Sun, 22 Mar 2009 20:51:58 GMT

I'm using ivf 10.1

The error is trivial. Simply, I was surprised that is not detected at compile time.

Perhaps an formated output can not be detected,but I thought that

print a

is an easily detectable error

Re: format syntax error

lklawrie — Sun, 22 Mar 2009 21:37:53 GMT

variable a could just as easily be defined as "('type this here')"

and thus print a would produce:

type this here

on the output line.

in old style fortran, any kind of variable could hold a string. that's why i say it might be detected during runtime but not perhaps during compile time.

Linda

Re: format syntax error

Steven_L_Intel1 — Mon, 23 Mar 2009 19:49:37 GMT

When I compile this program:

[plain]      print a
      end[/plain]

I get:

t.f90(1): error #6304: This format specifier must be of type INTEGER.
print a
------------^
compilation aborted for t.f90 (code 1)

The syntax of the PRINT statement is:

PRINT format [, output-item-list]

Now here's where it gets interesting. When you look at the F2003 standard, format is allowed to be one of:

default-char-expr
label
*

If it's a character expression (could be a variable), then the expression contains a format string. Label and * are obvious. But what's this about INTEGER? F2003 doesn't allow that.

But.. F77 does! In F77 (and F90), format is allowed to be an integer variable that has been ASSIGNed a label. Assigned GOTO and labels has been deleted from the language, but Intel Fortran still supports it. If I declare variable a to be an integer and compile with standards checking, I get this:

t.f90(2): warning #7358: Assigned FORMAT specifiers have been deleted in Fortran 2003.
print a
-----------^
t.f90(2): error #5503: Variable 'A' has not been assigned a label in this program unit.
print a
-----------^

But I note that if I don't ask for standards checking, I still get the second error.

So.. I assume that in Luis' program, variable a is declared character. Depending on what is in that character string, one might see almost anything at output, though usually you should see a "format syntax error". And indeed that's the title of this thread.

I would not expect the debugger to do anything with this. The program should generate a run-time error.

Re: format syntax error

TimP — Mon, 23 Mar 2009 20:04:51 GMT

Certain compilers, such as gfortran, will check the contents of a constant format string at compile time. Some of those checks happen with ifort only at run time, perhaps only when -check format has been set at compile time, and only when use of the format is attempted. The run-time check has the advantage of applying to variable as well as constant formats, but the disadvantage of not catching problems not exposed by a test run. The function of the debugger would be to help determine what led up to the problem, perhaps not needed in the present case.

Re: format syntax error

Luis2 — Tue, 24 Mar 2009 21:14:45 GMT

I would not expect the debugger to do anything with this. The program should generate a run-time error.

Yes, in my first post I should have written compiler, not debugger

In my little program a is a character

program main
character(len=5) a; a='foo' ; print a
end program

but the compiler does not catch any error, as expected the program crash when I run it.

It really is a bug when I was writing a code, I Do not expect the statement works in a different way.

Re: format syntax error

Peter — Tue, 24 Mar 2009 22:40:23 GMT

Quoting - Luis

Oh!!... That makes a lot of difference when you say 'debugger' instead of 'complier'.

Possibly it might be expecting a namelist, while it is compiling; when you debug it gets upset since it wasnt namelist ! Thesyntax for Print for namelist is
print nml
where
nml=Is the nonkeyword form of a namelist specifier (no NML=) indicating namelist formatting.

This might be a possibility only!

Re: format syntax error

Steven_L_Intel1 — Tue, 24 Mar 2009 23:35:05 GMT

I already explained that this program is perfectly valid Fortran syntax, which is why the compiler did not complain. It thought you had a run-time format string in variable A. Since you didn't, you got an error at run-time.

Re: format syntax error

Luis2 — Sat, 28 Mar 2009 15:29:07 GMT

I understand

program main
character(len=5) a
a='("foo")'
print a ! foo
end program

Thank you