diff --git a/libc/cmake/modules/LLVMLibCCheckCpuFeatures.cmake b/libc/cmake/modules/LLVMLibCCheckCpuFeatures.cmake
--- a/libc/cmake/modules/LLVMLibCCheckCpuFeatures.cmake
+++ b/libc/cmake/modules/LLVMLibCCheckCpuFeatures.cmake
@@ -44,44 +44,44 @@
   set(${output_var} ${tmp} PARENT_SCOPE)
 endfunction()
 
-# Generates a cpp file to introspect the compiler defined flags.
-function(_generate_check_code)
+# Generates cpp files to introspect the compiler defined flags.
+set(AVAILABLE_CPU_FEATURES "")
+if(LIBC_CROSSBUILD)
+  # If we are doing a cross build, we will just assume that all CPU features
+  # are available.
+  set(AVAILABLE_CPU_FEATURES ${ALL_CPU_FEATURES})
+else()
+  set(CMAKE_TRY_COMPILE_TARGET_TYPE STATIC_LIBRARY)
   foreach(feature IN LISTS ALL_CPU_FEATURES)
-    set(DEFINITIONS
-        "${DEFINITIONS}
-#ifdef __${feature}__
-    \"${feature}\",
-#endif")
-  endforeach()
-  configure_file(
-    "${LIBC_SOURCE_DIR}/cmake/modules/cpu_features/check_cpu_features.cpp.in"
-    "cpu_features/check_cpu_features.cpp" @ONLY)
-endfunction()
-_generate_check_code()
+    set(CPU_FEATURE_CHECK_SOURCE "
+        int main() {
+        #ifdef __${feature}__
+          return 0;
+        #else
+          __## syntax error ##__
+        #endif
+        }")
+    configure_file(
+      "${LIBC_SOURCE_DIR}/cmake/modules/cpu_features/check_cpu_features.cpp.in"
+      "check_cpu_features/check_cpu_feature_${feature}.cpp" @ONLY
+    )
+    try_compile(
+      has_feature ${CMAKE_CURRENT_BINARY_DIR}/cpu_features
+      ${CMAKE_CURRENT_BINARY_DIR}/check_cpu_features/check_cpu_feature_${feature}.cpp
+      COMPILE_DEFINITIONS ${LIBC_COMPILE_OPTIONS_NATIVE}
+    )
+  if(has_feature)
+    list(APPEND AVAILABLE_CPU_FEATURES ${feature})
+  endif()
+endforeach()
+endif()
 
-set(LIBC_CPU_FEATURES "" CACHE PATH "Host supported CPU features")
+set(LIBC_CPU_FEATURES ${AVAILABLE_CPU_FEATURES} CACHE STRING "Host supported CPU features")
 
-if(LIBC_CROSSBUILD)
-  _intersection(cpu_features "${ALL_CPU_FEATURES}" "${LIBC_CPU_FEATURES}")
-  if(NOT "${cpu_features}" STREQUAL "${LIBC_CPU_FEATURES}")
-    message(FATAL_ERROR "Unsupported CPU features: ${cpu_features}")
-  endif()
+_intersection(cpu_features "${AVAILABLE_CPU_FEATURES}" "${LIBC_CPU_FEATURES}")
+if(NOT "${cpu_features}" STREQUAL "${LIBC_CPU_FEATURES}")
+  message(FATAL_ERROR "Unsupported CPU features: ${cpu_features}")
+else()
   message(STATUS "Set CPU features: ${cpu_features}")
   set(LIBC_CPU_FEATURES "${cpu_features}")
-else()
-  # Populates the LIBC_CPU_FEATURES list from host.
-  try_run(
-    run_result compile_result "${CMAKE_CURRENT_BINARY_DIR}/check_${feature}"
-    "${CMAKE_CURRENT_BINARY_DIR}/cpu_features/check_cpu_features.cpp"
-    COMPILE_DEFINITIONS ${LIBC_COMPILE_OPTIONS_NATIVE}
-    COMPILE_OUTPUT_VARIABLE compile_output
-    RUN_OUTPUT_VARIABLE run_output)
-  if("${run_result}" EQUAL 0)
-    message(STATUS "Set CPU features: ${run_output}")
-    set(LIBC_CPU_FEATURES "${run_output}")
-  elseif(NOT ${compile_result})
-    message(FATAL_ERROR "Failed to compile: ${compile_output}")
-  else()
-    message(FATAL_ERROR "Failed to run: ${run_output}")
-  endif()
 endif()
diff --git a/libc/cmake/modules/cpu_features/check_cpu_features.cpp.in b/libc/cmake/modules/cpu_features/check_cpu_features.cpp.in
--- a/libc/cmake/modules/cpu_features/check_cpu_features.cpp.in
+++ b/libc/cmake/modules/cpu_features/check_cpu_features.cpp.in
@@ -1,32 +1 @@
-#include <stdio.h>
-#include <stdlib.h>
-
-// This file is instantiated by CMake.
-// DEFINITIONS below is replaced with a set of lines like so:
-//   #ifdef __SSE2__
-//     "SSE2",
-//   #endif
-//
-// This allows for introspection of compiler definitions.
-// The output of the program is a single line of semi colon separated feature
-// names.
-
-// MSVC is using a different set of preprocessor definitions for 
-// SSE and SSE2, see _M_IX86_FP in
-// https://docs.microsoft.com/en-us/cpp/preprocessor/predefined-macros
-
-int main(int, char **) {
-  const char *strings[] = {
-      @DEFINITIONS@
-      // If DEFINITIONS turns out to be empty, we don't want to list
-      // an empty array. So, we add an end of list marker.
-      "<end_of_feature_list>"
-  };
-  const size_t size = sizeof(strings) / sizeof(strings[0]);
-  for (size_t i = 0; i < size; ++i) {
-    if (i)
-      putchar(';');
-    fputs(strings[i], stdout);
-  }
-  return EXIT_SUCCESS;
-}
+@CPU_FEATURE_CHECK_SOURCE@