can't build libsigrok (Slackware current)

Hi, I upgraded Slackware current today and rebuilt the prerequisites for libsigrok, but I get an error building libsigrok. I have included the last few lines of the build hoping that it will help. Any help/suggestions are greatly appreciated. Thank you.

Code:64752 | rb_define_method(SwigClassConfigKey.klass, "description", VALUEFUNC(_wrap_ConfigKey_description), -1);
| ^~~~~~~~~
bindings/ruby/classes_wrap.cpp:64759:70: error: _wrap_ConfigKey_identifier_get' was not declared in this scope; did you mean sigrok_ConfigKey_identifier_get'?
64759 | rb_define_method(SwigClassConfigKey.klass, "identifier", VALUEFUNC(_wrap_ConfigKey_identifier_get), -1);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/ruby-2.7.0/ruby/ruby.h:2777:77: note: in definition of macro rb_define_method'
2777 | #define rb_define_method(m, n, f, a) rb_define_method_tmpl<a>::define(m, n, f)
| ^
bindings/ruby/classes_wrap.cpp:64759:60: note: in expansion of macro VALUEFUNC'
64759 | rb_define_method(SwigClassConfigKey.klass, "identifier", VALUEFUNC(_wrap_ConfigKey_identifier_get), -1);
| ^~~~~~~~~
make[1]: *** [Makefile:5062: bindings/ruby/classes_wrap.o] Error 1
make: *** [Makefile:1906: all] Error 2

libsigrok: