Unable to build DEVELOPMENT kernel from macOS 15.2 onwards

[peternguyen93]

Hi there,

I noticed that we can't compile DEVELOPMENT kernel since Apple added a verification step for UBSAN pointer overflow which is main reason to cause building progress failure.
Here is the full error output

error: UBSan verifier failure for /Users/peternguyen/exSSD/Sources/audit/darwin-xnu-build2/xnu/osfmk/vm/vm_sanitize.c:
error:     ; /Users/peternguyen/exSSD/Sources/audit/darwin-xnu-build2/xnu/osfmk/vm/vm_sanitize.c:1470
error:     ; TEST_UT_TYPE_ABI(vm_behavior_t, vm_behavior_ut, equal_scalar);
error:     		0000000000000b0c:  ARM64_RELOC_BRANCH26	___ubsan_handle_pointer_overflow
error:     ; /Users/peternguyen/exSSD/Sources/audit/darwin-xnu-build2/xnu/osfmk/vm/vm_sanitize.c:1470
error:     ; TEST_UT_TYPE_ABI(vm_behavior_t, vm_behavior_ut, equal_scalar);
error:     		0000000000000b5c:  ARM64_RELOC_BRANCH26	___ubsan_handle_pointer_overflow
error:     ; /Users/peternguyen/exSSD/Sources/audit/darwin-xnu-build2/xnu/osfmk/vm/vm_sanitize.c:1470
error:     ; TEST_UT_TYPE_ABI(vm_behavior_t, vm_behavior_ut, equal_scalar);
error:     		0000000000000ba8:  ARM64_RELOC_BRANCH26	___ubsan_handle_pointer_overflow
error:     ; /Users/peternguyen/exSSD/Sources/audit/darwin-xnu-build2/xnu/osfmk/vm/vm_sanitize.c:1470
error:     ; TEST_UT_TYPE_ABI(vm_behavior_t, vm_behavior_ut, equal_scalar);
error:     		0000000000000bec:  ARM64_RELOC_BRANCH26	___ubsan_handle_pointer_overflow
error:     ; /Users/peternguyen/exSSD/Sources/audit/darwin-xnu-build2/xnu/osfmk/vm/vm_sanitize.c:1470
error:     ; TEST_UT_TYPE_ABI(vm_behavior_t, vm_behavior_ut, equal_scalar);
error:     		0000000000000c2c:  ARM64_RELOC_BRANCH26	___ubsan_handle_pointer_overflow
error:     ; /Users/peternguyen/exSSD/Sources/audit/darwin-xnu-build2/xnu/osfmk/vm/vm_sanitize.c:1470
error:     ; TEST_UT_TYPE_ABI(vm_behavior_t, vm_behavior_ut, equal_scalar);
error:     		0000000000000c68:  ARM64_RELOC_BRANCH26	___ubsan_handle_pointer_overflow
error:     ; /Users/peternguyen/exSSD/Sources/audit/darwin-xnu-build2/xnu/osfmk/vm/vm_sanitize.c:1470
error:     ; TEST_UT_TYPE_ABI(vm_behavior_t, vm_behavior_ut, equal_scalar);
error:     		0000000000000ca0:  ARM64_RELOC_BRANCH26	___ubsan_handle_pointer_overflow
error:     ; /Users/peternguyen/exSSD/Sources/audit/darwin-xnu-build2/xnu/osfmk/vm/vm_sanitize.c:1470
error:     ; TEST_UT_TYPE_ABI(vm_behavior_t, vm_behavior_ut, equal_scalar);
error:     		0000000000000cd0:  ARM64_RELOC_BRANCH26	___ubsan_handle_pointer_overflow
error:     ; /Users/peternguyen/exSSD/Sources/audit/darwin-xnu-build2/xnu/osfmk/vm/vm_sanitize.c:1470

I tried few way to work around with it: disables UBSan, modified build system but none of these doesn't work.
I intended to create this issues if anyone know how to fix it.

Thanks

[BlueFalconHD]

I worked around it by commenting out the line enabling all UBSAN checks (relative to darwin-xnu-build.git) xnu/osfmk/conf/Makefile.template. There you should find something like:

#
# vm_sanitize/vm_sanitize_error_compat use the UBSan verifier to detect
# potential undefined behavior at compile time. The verifier inspects the
# compiled object files to detect calls to the UBSan minimal runtime.
#
# False positives are possible if checks are generated where UB is not actually
# possible. If possible, code should be re-architected to allow the compiler
# to optimize out the checks; if not __attribute__((nosanitize)) can be used.
#
# As of the time of writing, we enable all checks except the following:
#   `alignment` since it generates checks for calls to os_xyz_overflow()
#   `bool` since it generates checks most times bools are used
#   `function` since it generates checks for any non-trivial usage of function
#		pointers, and there is no way to do runtime type checking to eliminate
# 		these checks.
#   `null` since it generates NULL checks on typically non-null arguments.
#   	Marking these arguments using __attribute__(nonnull) may have an
#		undesired effect of optimizing out explicitly written NULL checks.
#   `unreachable` since it generates a check after each panic()
#   `obj-cast`,`return`,`vptr` since they are not relevant to C code
#
VM_UBSAN_CHECKS = bounds, builtin, enum, float-cast-overflow, \
	float-divide-by-zero, implicit-signed-integer-truncation, \
	implicit-unsigned-integer-truncation, integer-divide-by-zero, \
	nonnull-attribute, nullability-arg, nullability-assign, nullability-return, \
	object-size, pointer-overflow, returns-nonnull-attribute, shift, \
	signed-integer-overflow, unsigned-integer-overflow, unsigned-shift-base, \
	vla-bound
VM_UBSAN_FLAGS = -fsanitize=$(subst ${} ${},,${VM_UBSAN_CHECKS})

Comment out this line:

VM_UBSAN_FLAGS = -fsanitize=$(subst ${} ${},,${VM_UBSAN_CHECKS})