Return to debugging CVS log

Up to [CSRG BSD Unix] / 43BSDTahoe / new / help / src / f77

Annotation of 43BSDTahoe/new/help/src/f77/debugging, revision 1.1

1.1     ! root        1: .TI F77/DEBUGGING "Sep. 4, 1985"
        !             2: Debugging Aids for F77 Programs
        !             3: 
        !             4: The first step in debugging is to understand the error message you
        !             5: are getting.  See "help f77 error_msgs" for advice on that.
        !             6: 
        !             7: There are several utilities that can be used in debugging.
        !             8: If you have a core dump, use the debugger, dbx, to look at the core dump.
        !             9: If you compiled and loaded with the -g flag, dbx can be used to tell
        !            10: the line at which your program failed and to display the values of
        !            11: variables.  Dbx can also be used to set break points or single step a
        !            12: program and do interactive debugging.
        !            13: 
        !            14: If you did not compile with the -g flag,
        !            15: dbx will still tell you which subroutines were active at the time
        !            16: of the failure.  See "help f77 dbx" and "man dbx" for more information.
        !            17: 
        !            18: If you might be exceeding the bounds of an array,
        !            19: you can use f77's -C flag to check for subscripts out of range.
        !            20: 
        !            21: The 'nm' utility is useful in telling which procedures are referenced
        !            22: in which '.o' files.  Thus if the loader issues a message like:
        !            23: 
        !            24: .nf
        !            25:        Undefined:
        !            26:        _subr_
        !            27: .fi
        !            28: 
        !            29: and you don't know where subr() is called, the command:
        !            30: 
        !            31:        nm -og *.o | grep subr
        !            32: 
        !            33: will tell you which '.o' files in this directory reference subr().
        !            34: 
        !            35: The -M flag can be used to tell out of which archive or library a '.o'
        !            36: file is loaded.

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.