ERROR::PASS4(7stap)ERROR::PASS4(7stap)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 func‐
tions, types, or macros referenced by systemtap. Upstream
builds of systemtap are often quickly updated to include rele‐
vant 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 com‐
piler errors.
incompatible embedded-C code
The interface standards between systemtap-generated code and
embedded-C code occasionally change. For example, before ver‐
sion 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 stan‐
dards, or use the stap --compatible=VERSION option to make sys‐
temtap use a different one.
GATHERING MORE INFORMATION
It may be necessary to run systemtap with -k or -p3 to examine the gen‐
erated C code. Increasing the verbosity of pass-4 with an option such
as --vp 0001 can also help pinpoint the problem.
SEE ALSOstap(1), error::reporting(7stap)ERROR::PASS4(7stap)