NAME

       error::pass4 - systemtap pass-4 errors

DESCRIPTION

       Errors that occur during pass 4 (compilation) have generally only a few causes:

       kernel or OS version changes
              The  systemtap  runtime and embedded-C fragments in the tapset library are designed to be portable
              across a wide range of OS versions.  However, incompatibilities can occur  when  some  OS  changes
              occur,  such  as  kernel  modifications  that  change  functions,  types,  or macros referenced by
              systemtap.  Upstream builds of systemtap are often quickly updated to include relevant  fixes,  so
              try  getting  or  making  an  updated  build.   If  the  issue persists, report the problem to the
              systemtap developers.

       buggy embedded-C code
              Embedded-C code in your own guru-mode script cannot be checked by systemtap, and is passed through
              verbatim to the compiler.  Errors in such snippets of code may be found during the pass-4 compiler
              invocation, though may be hard to identify by the compiler errors.

       incompatible embedded-C code
              The interface standards between systemtap-generated code and embedded-C code occasionally  change.
              For example, before version 1.8, arguments were passed using macros THIS->foo and THIS->__retvalue
              but from version 1.8 onward, using STAP_ARG_foo and STAP_RETVALUE.  Adjust your embedded-C code to
              current  standards,  or use the stap --compatible=VERSION option to make systemtap use a different
              one.

GATHERING MORE INFORMATION

       It may be necessary to run systemtap with -k or -p3 to examine the  generated  C  code.   Increasing  the
       verbosity of pass-4 with an option such as --vp 0001 can also help pinpoint the problem.

SEE ALSO

       stap(1), error::reporting(7stap)

                                                                                             ERROR::PASS4(7stap)