systemtap build of signals script fails

[i30817]

i30817@AIVAS:~$ sudo stap sigkill.stp > process.txt
/tmp/stapXgPFfW/stap_d2a2e82b4e48884fc1a41654236e4050_17396_src.c: In function ‘function_uid’:
/tmp/stapXgPFfW/stap_d2a2e82b4e48884fc1a41654236e4050_17396_src.c:1375:16: error: incompatible types when assigning to type ‘int64_t’ from type ‘kuid_t’
  STAP_RETVALUE = current_uid();
                ^
make[1]: *** [/tmp/stapXgPFfW/stap_d2a2e82b4e48884fc1a41654236e4050_17396_src.o] Error 1
make: *** [_module_/tmp/stapXgPFfW] Error 2
WARNING: kbuild exited with status: 2
Pass 4: compilation failed. [man error::pass4]
Tip: /usr/share/doc/systemtap/README.Debian should help you get started.

from this script:
probe signal.send {
  if (sig_name == "SIGKILL" && pid_name == "java")
    printf("%s was sent to %s (pid:%d) by %s uid:%d\n",
           sig_name, pid_name, sig_pid, execname(), uid())
}

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: systemtap 2.3-1ubuntu1
ProcVersionSignature: Ubuntu 3.13.0-14.34-generic 3.13.5
Uname: Linux 3.13.0-14-generic x86_64
ApportVersion: 2.13.2-0ubuntu5
Architecture: amd64
CurrentDesktop: GNOME
Date: Sun Mar 2 17:46:55 2014
InstallationDate: Installed on 2014-01-17 (43 days ago)
InstallationMedia: Ubuntu-GNOME 14.04 "Trusty Tahr" - Alpha amd64 (20140117)
SourcePackage: systemtap
UpgradeStatus: No upgrade log present (probably fresh install)

[i30817 (i30817)]

it can be avoided in this example by not using uid() in the function

[Frank Ch. Eigler (fche)]

Hi -

> /tmp/stapXgPFfW/stap_d2a2e82b4e48884fc1a41654236e4050_17396_src.c:1375:16: error: incompatible types when assigning to type ‘int64_t’ from type ‘kuid_t’
> STAP_RETVALUE = current_uid();
> ^
[...]

Please see upstream commits c91d2e7cc99 and 0d135d775e.

- FChE

[i30817 (i30817)]

Thank you Frank.

[Emanuele Rocca (ema)]

sigkill.stp works fine with systemtap 4.2-3 from focal.