Example won't compile for Arduino Portenta

Compile command: arduino-cli compile ~/Arduino/libraries/LinkedList/examples/ClassList/ClassList.pde -b arduino:mbed_portenta:envie_m7 --libraries ~/Arduino/libraries/
Errors:
"
/home/cellula/Arduino/libraries/LinkedList/examples/ClassList/ClassList.ino: In function 'void setup()':
/home/cellula/Arduino/libraries/LinkedList/examples/ClassList/ClassList.ino:49:15: error: 'class LinkedList<Animal*>' has no member named 'add'
myAnimalList.add(cat);
^~~
/home/cellula/Arduino/libraries/LinkedList/examples/ClassList/ClassList.ino:50:15: error: 'class LinkedList<Animal*>' has no member named 'add'
myAnimalList.add(emu);
^~~
/home/cellula/Arduino/libraries/LinkedList/examples/ClassList/ClassList.ino:51:15: error: 'class LinkedList<Animal*>' has no member named 'add'
myAnimalList.add(dog);
^~~
/home/cellula/Arduino/libraries/LinkedList/examples/ClassList/ClassList.ino: In function 'void loop()':
/home/cellula/Arduino/libraries/LinkedList/examples/ClassList/ClassList.ino:57:28: error: 'class LinkedList<Animal*>' has no member named 'size'
Serial.print(myAnimalList.size());
^~~~
/home/cellula/Arduino/libraries/LinkedList/examples/ClassList/ClassList.ino:62:34: error: 'class LinkedList<Animal*>' has no member named 'size'
for(int i = 0; i < myAnimalList.size(); i++){
^~~~
/home/cellula/Arduino/libraries/LinkedList/examples/ClassList/ClassList.ino:65:25: error: 'class LinkedList<Animal*>' has no member named 'get'
animal = myAnimalList.get(i);
^~~

Error during build: exit status 1
"

Arduino CLI version 0.20.2
Arduino Portenta core version 2.6.1
LinkedList library version 1.3.2

Compiles for Arduino Mega after deleting tests.cpp.

Start by running the reported arduino-cli compile command for examples/ClassList/ClassList.ino on the Portenta core, then inspect the example and _tests.cpp, since removing _tests.cpp is reported to make the library compile on Mega. Compare the resulting build behavior across Portenta and Mega; done means the ClassList example compiles on Portenta without breaking the Mega build.