Error building module (possibly related to clang)

[neuromante]

My system is Openmandriva ROME on x86_64 architecture. When I try to build the module (sudo dkms autoinstall) I get an error. This is the relevant output:

DKMS make.log for rtl88x2bu-git for kernel 6.2.6-desktop-1omv2390 (x86_64) lun 3 apr 2023, 11:46:21, CEST make ARCH=x86_64 CROSS_COMPILE= -C /lib/modules/6.2.6-desktop-1omv2390/build M=/var/lib/dkms/rtl88x2bu/git/build modules warning: the compiler differs from the one used to build the kernel The kernel was built by: OpenMandriva 15.0.7-3 clang version 15.0.7 (/builddir/build/BUILD/llvm-project-15.0.7.src/clang c5b761db9d28a8cbbafbaa455d57066c5a0e42bc) You are using: gcc (GCC) 12.2.0 20220819 (OpenMandriva) CC [M] /var/lib/dkms/rtl88x2bu/git/build/core/rtw_cmd.o CC [M] /var/lib/dkms/rtl88x2bu/git/build/core/rtw_security.o CC [M] /var/lib/dkms/rtl88x2bu/git/build/core/rtw_debug.o CC [M] /var/lib/dkms/rtl88x2bu/git/build/core/rtw_io.o gcc: error: unrecognized command-line option ‘-Qunused-arguments’ gcc: error: unrecognized command-line option ‘-Qunused-arguments’ gcc: error: unrecognized command-line option ‘-Qunused-arguments’ gcc: error: unrecognized command-line option ‘-Qunused-arguments’ gcc: error: unrecognized command-line option ‘-mretpoline-external-thunk’ gcc: error: unrecognized command-line option ‘-mretpoline-external-thunk’ gcc: error: unrecognized command-line option ‘-mretpoline-external-thunk’ gcc: error: unrecognized command-line option ‘-mretpoline-external-thunk’ gcc: error: unrecognized command-line option ‘-fsplit-lto-unit’ gcc: error: unrecognized command-line option ‘-fsplit-lto-unit’ gcc: error: unrecognized command-line option ‘-fsplit-lto-unit’ gcc: error: unrecognized command-line option ‘-fsplit-lto-unit’ gcc: error: unrecognized command-line option ‘-Wformat-invalid-specifier’ gcc: error: unrecognized command-line option ‘-Wformat-invalid-specifier’ gcc: error: unrecognized command-line option ‘-Wformat-invalid-specifier’ gcc: error: unrecognized command-line option ‘-Wformat-invalid-specifier’ gcc: error: unrecognized command-line option ‘-Wformat-insufficient-args’ make[2]: *** [scripts/Makefile.build:252: /var/lib/dkms/rtl88x2bu/git/build/core/rtw_cmd.o] Error 1 make[2]: *** Attesa per i processi non terminati.... gcc: error: unrecognized command-line option ‘-Wformat-insufficient-args’ make[2]: *** [scripts/Makefile.build:252: /var/lib/dkms/rtl88x2bu/git/build/core/rtw_security.o] Error 1 gcc: error: unrecognized command-line option ‘-Wformat-insufficient-args’ make[2]: *** [scripts/Makefile.build:252: /var/lib/dkms/rtl88x2bu/git/build/core/rtw_debug.o] Error 1 gcc: error: unrecognized command-line option ‘-Wformat-insufficient-args’ make[2]: *** [scripts/Makefile.build:252: /var/lib/dkms/rtl88x2bu/git/build/core/rtw_io.o] Error 1 make[1]: *** [Makefile:2021: /var/lib/dkms/rtl88x2bu/git/build] Error 2 make: *** [Makefile:2455: modules] Error 2

Is there some change I have to make to makefile? Thanks

[RinCat]

warning: the compiler differs from the one used to build the kernel The kernel was built by: OpenMandriva 15.0.7-3 clang version 15.0.7 (/builddir/build/BUILD/llvm-project-15.0.7.src/clang c5b761db9d28a8cbbafbaa455d57066c5a0e42bc) You are using: gcc (GCC) 12.2.0 20220819 (OpenMandriva)

Hi, you must use same compiler and same version as the kernel. And set make CC=clang ...

[neuromante]

Thanks...but (and sorry for the dumbness) which file do I have to edit to put the variable? Thanks again Rincat

[RinCat]

You don't need to edit any file, just add CC=clang after the make.

[neuromante]

Yes BUT if I want to use dkms for automatic module building?

[RinCat]

Try add CC = clang at the top of Makefile

[neuromante]

I tried but this is the output: make ARCH=x86_64 CROSS_COMPILE= -C /lib/modules/6.2.6-desktop-1omv2390/build M=/usr/src/rtl88x2bu-git modules warning: the compiler differs from the one used to build the kernel The kernel was built by: OpenMandriva 15.0.7-3 clang version 15.0.7 (/builddir/build/BUILD/llvm-project-15.0.7.src/clang c5b761db9d28a8cbbafbaa455d57066c5a0e42bc) You are using: gcc (GCC) 12.2.0 20220819 (OpenMandriva) CC [M] /usr/src/rtl88x2bu-git/core/rtw_cmd.o clang-15: error: unknown argument: '-mpreferred-stack-boundary=3' clang-15: error: unknown argument: '-mindirect-branch-cs-prefix' clang-15: warning: optimization flag '-falign-jumps=1' is not supported [-Wignored-optimization-argument] make[2]: *** [scripts/Makefile.build:252: /usr/src/rtl88x2bu-git/core/rtw_cmd.o] Error 1 make[1]: *** [Makefile:2021: /usr/src/rtl88x2bu-git] Error 2 It seems that the compiler will remain the same even with the variable at the top of the Makefile...

[neuromante]

Update: it compiles only if I type "sudo make CC=clang" in the src directory. Dkms seems to have issues

[RinCat]

Edit dkms.conf and change MAKE="'make' -j$(nproc) KVER=${kernelver} KSRC=/lib/modules/${kernelver}/build" to MAKE="'make' -j$(nproc) CC=clang KVER=${kernelver} KSRC=/lib/modules/${kernelver}/build"