diff --git a/tools/pioasm/CMakeLists.txt b/tools/pioasm/CMakeLists.txt
index df80530..322408a 100644
--- a/tools/pioasm/CMakeLists.txt
+++ b/tools/pioasm/CMakeLists.txt
@@ -36,8 +36,11 @@ endif()
 
 target_include_directories(pioasm PRIVATE ${CMAKE_CURRENT_LIST_DIR} ${CMAKE_CURRENT_LIST_DIR}/gen)
 
-if (MSVC)
+if (MSVC OR
+    (WIN32 AND NOT MINGW AND (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")))
     target_compile_definitions(pioasm PRIVATE YY_NO_UNISTD_H)
+endif()
+if (MSVC)
     target_compile_options(pioasm PRIVATE "/std:c++latest")
 endif()