diff --git a/spec/ruby/core/process/fixtures/clocks.rb b/spec/ruby/core/process/fixtures/clocks.rb
index 7537cfaba8..55ee0f294f 100644
--- a/spec/ruby/core/process/fixtures/clocks.rb
+++ b/spec/ruby/core/process/fixtures/clocks.rb
@@ -11,6 +11,10 @@ def self.clock_constants
       clocks -= [:CLOCK_BOOTTIME_ALARM, :CLOCK_REALTIME_ALARM]
     end
 
+    clocks = clocks.reject { |clock, value|
+      [:CLOCK_BOOTTIME, :CLOCK_TAI].include?(clock)
+    }
+
     clocks.sort.map { |c|
       [c, Process.const_get(c)]
     }
-- 
2.21.0