Index: meson/arch/arm64/meson.build
===================================================================
--- meson/arch/arm64/meson.build	(revision 068dd86441c1b48ecb3ea38e369c81ba75496a5c)
+++ meson/arch/arm64/meson.build	(revision 24cf6694d6f651e6f8a941e34ceef392a3ef74e6)
@@ -28,5 +28,9 @@
 #
 
-arch_uspace_c_args = [ '-D__LE__', '-fno-omit-frame-pointer', '-mno-outline-atomics' ]
+arch_uspace_c_args = [
+	'-D__LE__',
+	'-fno-omit-frame-pointer',
+	cc.get_supported_arguments(['-mno-outline-atomics']),
+]
 arch_kernel_c_args = arch_uspace_c_args + [ '-march=armv8-a+nofp+nosimd', '-mgeneral-regs-only' ]
 arch_kernel_link_args = [ '-nostdlib' ]