[PD] UBUNTU - problem with pd vanilla externals

[oliver]

hi,

i just installed pd on a UBUNTU notebook and i am getting error messages 
when opening the help-intro.pd patch.
some vanilla objects (sigmund~, bonk~, choice) can't be loaded and give 
the following error messages:

/usr/lib/puredata/extra/sigmund~/sigmund~.pd_linux: 
/usr/lib/puredata/extra/sigmund~/sigmund~.pd_linux: undefined symbol: 
__pow_finite
/usr/lib/puredata/tcl/../extra/sigmund~/sigmund~.pd_linux: 
/usr/lib/puredata/tcl/../extra/sigmund~/sigmund~.pd_linux: undefined 
symbol: __pow_finite
  sigmund~
... couldn't create

the errors for the other 2 objects are similar with the following 
differences:

[bonk~]: undefined symbol: __exp_finite
[choice]: undefined symbol: __logf_finite

these are my specs:

OS:
Distributor ID: Ubuntu
Description:    Ubuntu 20.04.2 LTS
Release:        20.04
Codename:       focal

PD:
Pd-0.50.2 ("") compiled for Debian (0.50.2-3) on 2020/02/24 at 22:30:39 UTC


can somebody help me ?

thanks a lot in advance

oliver