`KERNEL_CC=clang CC=clang make`

[dreirund]

Ahoj,

build for clang-build Linux 6.10.10 fails for me -- make system is trying to use gcc.

I try build as follows:

git clone https://github.com/freemed/tty0tty.git
cd tty0tty/module
CC=clang make

KERNEL_CC=clang CC=clang make fails with

make -C /lib/modules/6.10.10-xanmod-customconfig-clang/build M=/tmp/tty0tty/module modules
make[1]: Entering directory '/usr/lib/modules/6.10.10-xanmod-customconfig-clang/build'
warning: the compiler differs from the one used to build the kernel
  The kernel was built by: clang version 18.1.8
  You are using:           gcc (GCC) 14.2.1 20240910
  CC [M]  /tmp/tty0tty/module/tty0tty.o
gcc: error: unrecognized argument to ‘-fsanitize=’ option: ‘kcfi’
gcc: error: unrecognized command-line option ‘-mretpoline-external-thunk’
make[3]: *** [scripts/Makefile.build:244: /tmp/tty0tty/module/tty0tty.o] Error 1
make[2]: *** [/usr/lib/modules/6.10.10-xanmod-customconfig-clang/build/Makefile:2080: /tmp/tty0tty/module] Error 2
make[1]: *** [Makefile:240: __sub-make] Error 2
make[1]: Leaving directory '/usr/lib/modules/6.10.10-xanmod-customconfig-clang/build'
make: *** [Makefile:26: default] Error 2

The kernel is built with clang, but this seems to be ignored.

git describe --tags of the cloned tty0tty source shows 1.2-59-gac540b8, i.e. at commit ac540b8.

---

Edit: With dkms, it works, though.

Regards!

[stappersg]

patches welcome