diff --git a/test/lib/jit_support.rb b/test/lib/jit_support.rb
index 5977e84c1d..5e803e97bf 100644
--- a/test/lib/jit_support.rb
+++ b/test/lib/jit_support.rb
@@ -56,7 +56,7 @@ module JITSupport
     return @supported if defined?(@supported)
     @supported = UNSUPPORTED_COMPILERS.all? do |regexp|
       !regexp.match?(RbConfig::CONFIG['MJIT_CC'])
-    end && RbConfig::CONFIG["MJIT_SUPPORT"] != 'no' && !PENDING_RUBYCI_NICKNAMES.include?(ENV['RUBYCI_NICKNAME']) && !vs120_pdb_corrupted?
+    end && RbConfig::CONFIG["MJIT_SUPPORT"] != 'no' && !PENDING_RUBYCI_NICKNAMES.include?(ENV['RUBYCI_NICKNAME']) && !vs120_pdb_corrupted? && /mingw/ !~ RUBY_PLATFORM # TODO: remove mingw exclusion after investigation
   end
 
   # AppVeyor's Visual Studio 2013 is known to spuriously generate broken pch / pdb, like:
diff --git a/test/ruby/test_jit_debug.rb b/test/ruby/test_jit_debug.rb
index 179512fec6..0d357ee7e0 100644
--- a/test/ruby/test_jit_debug.rb
+++ b/test/ruby/test_jit_debug.rb
@@ -5,6 +5,7 @@ return if ENV.key?('APPVEYOR')
 return if ENV.key?('RUBYCI_NICKNAME')
 return if ENV['RUBY_DEBUG']&.include?('ci') # ci.rvm.jp
 return if /mswin/ =~ RUBY_PLATFORM
+return if /darwin/ =~ RUBY_PLATFORM # TODO: remove this after investigation
 
 class TestJITDebug < TestJIT
   def setup