gcc-15 switched to C23

Tl;DR In November gcc merged the switch from C17 ( -std=gnu17 ) to C23 ( -std=c23 ) language standard used by default for C code. This will cause quite a few build failures in projects written in C . A few example fixes: libffi : optional va_start parameter. ncompress : void foo() changed the meaning to void foo(void) . ell bool , true and false are new keywords. And specifically false is not…