diff --git a/lib/Fuzzer/test/CMakeLists.txt b/lib/Fuzzer/test/CMakeLists.txt
index 1f9999f4401..7fa75a8abc5 100644
--- a/lib/Fuzzer/test/CMakeLists.txt
+++ b/lib/Fuzzer/test/CMakeLists.txt
@@ -226,6 +226,10 @@ set(TestBinaries ${TestBinaries} LLVMFuzzer-DSOTest)
 # Note this is done after declaring all tests so we can inform lit if any tests
 # need to be disabled.
 ###############################################################################
+set(LIBFUZZER_POSIX 1)
+if (MSVC)
+  set(LIBFUZZER_POSIX 0)
+endif()
 
 configure_lit_site_cfg(
   ${CMAKE_CURRENT_SOURCE_DIR}/lit.site.cfg.in
diff --git a/lib/Fuzzer/test/lit.cfg b/lib/Fuzzer/test/lit.cfg
index 745af0c3824..c3e7c3835d0 100644
--- a/lib/Fuzzer/test/lit.cfg
+++ b/lib/Fuzzer/test/lit.cfg
@@ -20,6 +20,12 @@ if config.has_lsan:
 else:
   lit_config.note('lsan feature unavailable')
 
+if sys.platform.startswith('win') or sys.platform.startswith('cygwin'):
+  config.available_features.add('windows')
+
+if config.is_posix:
+  config.available_features.add('posix')
+
 if sys.platform.startswith('linux'):
   # Note the value of ``sys.platform`` is not consistent
   # between python 2 and 3, hence the use of ``.startswith()``.
diff --git a/lib/Fuzzer/test/lit.site.cfg.in b/lib/Fuzzer/test/lit.site.cfg.in
index 03e86c487ca..069f2b72c0d 100644
--- a/lib/Fuzzer/test/lit.site.cfg.in
+++ b/lib/Fuzzer/test/lit.site.cfg.in
@@ -1,4 +1,5 @@
 config.test_exec_root = "@CMAKE_CURRENT_BINARY_DIR@"
 config.llvm_tools_dir = "@LLVM_TOOLS_DIR@"
 config.has_lsan = True if @HAS_LSAN@ == 1 else False
+config.is_posix = @LIBFUZZER_POSIX@
 lit_config.load_config(config, "@CMAKE_CURRENT_SOURCE_DIR@/lit.cfg")