U-boot and tumbleweed

i to all, im using u-boot (last release) and when compiling on tumbleweed i got this error:

  CC      cmd/pxe.o
  CC      cmd/setexpr.o
include/ctype.h:1:1: error: expected identifier or ‘(’ before numeric constant
    1 | linux/ctype.h
      | ^~~~~
make[1]: *** [scripts/Makefile.build:257: cmd/setexpr.o] Error 1
make: *** [Makefile:1863: cmd] Error 2

and I really don’t know how to solve this. Why? how in the earth should I know wherre to look? the file in fact is u-boot —> include ----->linux and the file is ctype.h but thats it!!!
any help?