NAME

       warning::debuginfo - systemtap missing-debuginfo warnings

DESCRIPTION

       For  many  symbolic  probing operations, systemtap needs DWARF debuginfo for the relevant binaries.  This
       often includes resolving function/statement probes, or $context variables  in  related  handlers.   DWARF
       debuginfo  may  be  found  in the original binaries built during compilation, or may have been split into
       separate files.  The SYSTEMTAP_DEBUGINFO_PATH environment variable  affects  where  systemtap  looks  for
       these files.

       If  your  operating system came from a distributor, check with them if debuginfo packages or variants are
       available.  If your distributor does not have debuginfo-equipped binaries at all, you may need to rebuild
       it.

       kernel debuginfo
              For scripts that target the kernel, systemtap may search for the vmlinux file created  during  its
              original  build.   This  is  distinct from the boot-loader's compressed/stripped vmlinuz file, and
              much larger.  If you have a hand-built kernel, make sure it was built with the CONFIG_DEBUG_INFO=y
              option.

       process debuginfo
              For scripts that target user-space, systemtap may search for debuginfo.  If  you  have  hand-built
              binaries, use CFLAGS=-g -O2 to compile them.

       unnecessary debuginfo
              In  some cases, a script may be altered to avoid requiring debuginfo.  For example, as script that
              uses probe syscall.*  probes could try instead probe nd_syscall.*  (for non-DWARF syscall):  these
              work  similarly,  and  use  more  intricate  (fragile)  tapset  functions  to  extract system call
              arguments.  Another option is use of compiled-in instrumentation such  as  kernel  tracepoints  or
              user-space  <sys/sdt.h>  markers  in libraries or executables, which do not require debuginfo.  If
              debuginfo was required for resolving a complicated $var->foo->bar expression, it may  be  possible
              to  use  @cast(var,"foo","foo.h")->foo->bar  to  synthesize  debuginfo for that type from a header
              file.

AUTOMATION

       On some platforms, systemtap may advise what commands to run, in  order  to  download  needed  debuginfo.
       Another  possibility  is  to  invoke  systemtap with the --download-debuginfo flag.  The stap-prep script
       included with systemtap may be able to download the appropriate kernel debuginfo.  Another possibility is
       to install and use a stap-server  remote-compilation  instance  on  a  machine  on  your  network,  where
       debuginfo and compilation resources can be centralized.  Try the stap --use-server option, in case such a
       server is already running.

SEE ALSO

       stap(1), stappaths(7), stap-server(8), strip(1), error::reporting(7stap) error::contextvars(7stap)

                                                                                       WARNING::DEBUGINFO(7stap)