This is to suppress warnings on headers that you do not have control over. for clang/gcc the flag is `-isystem` and for msvc its `external:I` [About msvc version](https://devblogs.microsoft.com/cppblog/broken-warnings-theory/)
This is to suppress warnings on headers that you do not have control over.
for clang/gcc the flag is
-isystemand for msvc itsexternal:IAbout msvc version