Problem with fltk from current in some projects not build

Hi , i have updated slackware64-current box.

I install fltk to build two projects , but the two fails with same messages , and im not see where is the problem.

Same projects, using fltk from SBo buidls fine , but not with fltk from slackware.

projects are
https://github.com/ChunshengZhao/inflator/releases
https://github.com/ChunshengZhao/feedingbottle/releases

error is same in two projects

https://pastebin.com/MePbSQst