From dbeb8ae02ac8dc3b7f34f21bd8633a936a398e9a Mon Sep 17 00:00:00 2001
From: Anton Maklakov <anton@espressif.com>
Date: Wed, 14 Nov 2018 19:45:14 +0800
Subject: [PATCH] cmake: fix the creation dummy main to avoid rebuilding

---
 tools/cmake/idf_functions.cmake | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/tools/cmake/idf_functions.cmake b/tools/cmake/idf_functions.cmake
index fd5fce0c7..6ae7698da 100644
--- a/tools/cmake/idf_functions.cmake
+++ b/tools/cmake/idf_functions.cmake
@@ -188,7 +188,10 @@ function(idf_add_executable)
         # Create a dummy file to work around CMake requirement of having a source
         # file while adding an executable
         add_executable(${exe_target} "${CMAKE_CURRENT_BINARY_DIR}/dummy_main_src.c")
-        file(WRITE ${CMAKE_CURRENT_BINARY_DIR}/dummy_main_src.c)
+        add_custom_command(OUTPUT dummy_main_src.c
+            COMMAND ${CMAKE_COMMAND} -E touch dummy_main_src.c
+            WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
+            VERBATIM)
 
         add_custom_target(dummy_main_src DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/dummy_main_src.c)