ghdl-yosys-plugin compilation failed

I am about to test GHDL and Yosys as a replacement of EDA proprietary design flows, for my students. My point is about VHDL synthesis.

I have a fresh install of several tools : trellis (ECP5), yosys, nexpnr, fujprog (ulx3s).

GHDL is also installed for a longer time but it is supposed to include synthesis also (--synth option works).

ghdl -v 
GHDL 1.0-dev (v0.37.0-208-g2c66a8bd) [Dunoon edition]
Compiled with GNAT Version: Community 2019 (20190517-83)
llvm code generator

It seems that I also need ghdl-yosys-plugin. However, the install does not work for me.

I get a bunch of error messages :

make GHDL=/opt/ghdl/bin/ghdl
yosys-config --exec --cxx -c --cxxflags -o ghdl.o src/ghdl.cc -fPIC -DYOSYS_ENABLE_GHDL -I/opt/ghdl/include -O
src/ghdl.cc:361:2: error: unknown type name 'Attribute'
        Attribute attr = get_first_attribute (inst);
        ^
src/ghdl.cc:361:19: error: use of undeclared identifier 'get_first_attribute'
        Attribute attr = get_first_attribute (inst);
                         ^
src/ghdl.cc:379:7: error: use of undeclared identifier 'Id_Posedge'; did you mean 'Id_Edge'?
        case Id_Posedge:
             ^~~~~~~~~~
             Id_Edge

etc

I am missing something. Can someone help ?

Thanks in advance JCLL