--- a/Telegram/gyp/PrecompiledHeader.cmake	2019-06-06 18:14:46.443138055 +0200
+++ b/Telegram/gyp/PrecompiledHeader.cmake	2019-06-06 18:15:45.874739539 +0200
@@ -114,7 +114,7 @@
       set(_compiler_FLAGS "@${_pch_c_flags_file}")
       add_custom_command(
         OUTPUT "${_output_c}"
-        COMMAND "${CMAKE_C_COMPILER}" ${_compiler_FLAGS} -x c-header -o "${_output_c}" -c "${_pchfile}"
+        COMMAND "${CMAKE_C_COMPILER}" ${_compiler_FLAGS} "$(C_FLAGS)" -x c-header -o "${_output_c}" -c "${_pchfile}"
         DEPENDS "${_pchfile}" "${_pch_c_flags_file}"
         IMPLICIT_DEPENDS C "${_pch_header}"
         COMMENT "Precompiling ${_name} for ${_target} (C)")
@@ -125,7 +125,7 @@
       set(_compiler_FLAGS "@${_pch_cpp_flags_file}")
       add_custom_command(
         OUTPUT "${_output_cxx}"
-        COMMAND "${CMAKE_CXX_COMPILER}" ${_compiler_FLAGS} -x c++-header -o "${_output_cxx}" -c "${_pchfile}"
+        COMMAND "${CMAKE_CXX_COMPILER}" ${_compiler_FLAGS} "$(CXX_FLAGS)" -x c++-header -o "${_output_cxx}" -c "${_pchfile}"
         DEPENDS "${_pchfile}" "${_pch_cpp_flags_file}"
         IMPLICIT_DEPENDS CXX "${_pch_header}"
         COMMENT "Precompiling header ${_name} for ${_target} (C++)")