Converted from .HLP to .HTML by HLPTOHTML.

fortran .HLP

Compilation_Errors

A diagnostic message issued by the compiler describes the detected error and, in some cases, contains an indication of the action taken by the compiler in response to the error.

Besides reporting errors detected in source program syntax, the compiler issues messages indicating errors that involve the compiler itself, such as I/O errors.

The severity-level classes of compilation error messages, in order of greatest to least severity, are as follows:

Code Description ---- -----------

F Fatal; must be corrected before the program can be compiled. No object file is produced.

E Error; should be corrected. An object file is produced, but the output or program result may be incorrect.

W Warning; should be investigated by checking the statements to which warning diagnostic messages refer. Warnings are issued for statements that use acceptable, but nonstandard, syntax and for statements corrected by the compiler. An object file is produced, but the program results may be incorrect. (If you specify /NOWARNINGS on the FORTRAN command line, you will not receive these messages.)

I Information; not an error message and does not call for corrective action. However, the informational message informs you that either a correct DEC Fortran statement may have unexpected results or you have used a DEC Fortran extension to FORTRAN-77.

The following examples show how compilation messages are displayed:

%FORT-W-FMTEXTCOM, Extra comma in format list [FORMAT (I3,)] in module MORTGAGE at line 13

%FORT-F-UNDSTALAB, Undefined statement label [66] in module MORTGAGE at line 19

Additional Information on:

Run_Time_Errors

Errors that occur during execution of your program are reported by diagnostic messages from the Run-Time Library. These messages can result from hardware conditions, file system errors, errors detected by RMS, errors that occur during transfer of data between the program and an internal record, computations that cause overflow or underflow, incorrect calls to the Run-Time Library, problems in array descriptions, and conditions detected by the operating system. Refer to the "VAX Run-Time Library Reference Manual" for more information.

In order of greatest to least severity, the three classes of run-time diagnostic messages are as follows:

Code Description ---- -----------

F Severe error; must be corrected. The program cannot complete execution and is terminated when the error is encountered.

E Error; should be corrected. The program may continue execution, but the output from this execution may be incorrect.

W Warning; should be investigated. The program continues executing, but output from this execution may be incorrect.

The following example shows how run-time messages are displayed:

%FOR-F-ADJARRDIM, adjustable array dimension error

In this Help file, the letter "C" after an error code indicates that program execution can continue immediately after the error if a user-written condition handler specifies that execution continue.

Additional Information on:

Vectorization_Errors

 The following errors identify when vectorization was inhibited and attempt to identify why it was inhibited. These messages are generated if the /VECTOR/SHOW=DATA_DEPENDENCES/DIAGNOSTICS qualifiers are specified. These errors are only generated to the diagnostic file, not to the listing file or terminal.

Unknown dependence using xxxx The compiler has analyzed the dependences between array references and is unable to determine the order in which the references must occur. Many times this is caused by not knowing the range of values possible for an expression used as part of the array index.

Nonuniform dependence The compiler has detected that the relative order of references to common memory locations, for two array references in the loop, are not uniform for all such locations. For example:

A(I) = B(I) * A(N-I)

Some locations are accessed first by A(I) and others by A(N-I).

Outer level vectorization inhibited The compiler has analyzed the dependences between array references at different DO-loop levels and is unable to determine the order in which the references must occur.

These errors relate to assertion declarations. See Section 6.2.1 in your performance guide for information on how to handle these errors.

Within LSE, you can use Review Mode to apply suggested assertions to handle these errors. To do so, move the cursor to the suggestion that you wish to use and press Ctrl/G. This instructs LSE to apply the suggestion to the source file. LSE then prompts for a confirmation that this change is desirable. If it is, answer YES and the suggestion will be inserted.