diff --git a/spec/ruby/core/process/clock_gettime_spec.rb b/spec/ruby/core/process/clock_gettime_spec.rb
index b690186ac3..56d75a04c9 100644
--- a/spec/ruby/core/process/clock_gettime_spec.rb
+++ b/spec/ruby/core/process/clock_gettime_spec.rb
@@ -2,13 +2,19 @@ require_relative '../../spec_helper'
 
 describe "Process.clock_gettime" do
   platform_is_not :windows do
-    Process.constants.select { |c|
-      c.to_s.start_with?('CLOCK_') &&
+    invalid_clocks = [
       # These require CAP_WAKE_ALARM and are not documented in clock_gettime(),
       # they return EINVAL if the permission is not granted.
-      c != :CLOCK_BOOTTIME_ALARM &&
-      c != :CLOCK_REALTIME_ALARM
-    }.each do |c|
+      :CLOCK_BOOTTIME_ALARM,
+      :CLOCK_REALTIME_ALARM,
+      # These don't work on Solaris
+      :CLOCK_PROCESS_CPUTIME_ID,
+      :CLOCK_THREAD_CPUTIME_ID,
+      :CLOCK_VIRTUAL,
+      :CLOCK_PROF,
+    ]
+
+    Process.constants.select { |c| c.to_s.start_with?('CLOCK_') && !invalid_clocks.include?(c) }.each do |c|
       it "can be called with Process::#{c}" do
         value = Process.const_get(c)
         Process.clock_gettime(value).should be_an_instance_of(Float)