BLD, BUG: Fix build failure for host flags e.g. -march=native on unsupported architectures

Author: seiko2plus

meson_cpu/meson.build

@@ -98,7 +98,7 @@ if host_machine.endian() == 'little' and cpu_family == 'ppc64'
   min_features = [VSX2]
 endif
 
-# Used by build option 'max'
+# Used by build option 'max/native/detect'
 max_features_dict = {
   'x86': X86_FEATURES,
   'x86_64': X86_FEATURES,
@@ -111,6 +111,11 @@ max_features = []
 foreach fet_name, fet_obj : max_features_dict
   max_features += [fet_obj]
 endforeach
+if max_features.length() == 0
+  message('Disabling CPU feature detection due to unsupported architecture: "' + cpu_family + '"')
+  CPU_CONF_BASELINE = 'none'
+  CPU_CONF_DISPATCH = 'none'
+endif
 
 parse_options = {
   'cpu-baseline': CPU_CONF_BASELINE,