clang 15 build error

From: Borislav Petkov

Date: Wed Oct 15 2025 - 10:33:27 EST


Hey,

before I go dig into this, any ideas? The likelyhood that you know what the
issue is, is high: :-P

That's 32-bit allnoconfig of latest Linus master with Ubuntu clang version
15.0.7:

mm/maccess.c:41:3: error: invalid output size for constraint '=a'
copy_from_kernel_nofault_loop(dst, src, size, u64, Efault);
^
mm/maccess.c:22:3: note: expanded from macro 'copy_from_kernel_nofault_loop'
__get_kernel_nofault(dst, src, type, err_label); \
^
./arch/x86/include/asm/uaccess.h:629:18: note: expanded from macro '__get_kernel_nofault'
__get_user_size(*((type *)(dst)), (__force type __user *)(src), \
^
mm/maccess.c:41:3: error: invalid output size for constraint '=a'
mm/maccess.c:22:3: note: expanded from macro 'copy_from_kernel_nofault_loop'
__get_kernel_nofault(dst, src, type, err_label); \
^
./arch/x86/include/asm/uaccess.h:629:18: note: expanded from macro '__get_kernel_nofault'
__get_user_size(*((type *)(dst)), (__force type __user *)(src), \
^
2 errors generated.
make[3]: *** [scripts/Makefile.build:287: mm/maccess.o] Error 1
make[3]: *** Waiting for unfinished jobs....
make[2]: *** [scripts/Makefile.build:556: mm] Error 2
make[2]: *** Waiting for unfinished jobs....
make[1]: *** [/home/amd/kernel/linux/Makefile:2010: .] Error 2
make: *** [Makefile:248: __sub-make] Error 2

--
Regards/Gruss,
Boris.

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