title: Is it possible to globally #define a macro? (for the real-time error checker to see)
body: <p>By &quot;macro&quot; I mean simple values like: &quot;#define FOO 123&quot;.</p>
  <p>I installed VS <strong>Code</strong> (not visual studio), and the C/C++ and Visual Intellicode extensions.</p>
  <p>I have a folder of a project created in another IDE which I'm still going to use to debug and more, specifically geared to certain embedded targets.
  That IDE and its config code generator / vendor libraries make use of the concept of <em>global defines</em>.
  (It's Eclipse based).
  E.g. there are some #define's which are visible by every source file without them including any headers for it: it gets passed to the compiler as well as the IDE's &quot;live&quot; error checking engine.</p>
  <p>Some of the header files that are auto-generated or come as a library from the vendor are set up such that e.g. such a global #define will select code for which concrete hardware target, out of a line of targets that's covered by the library, will be compiled.</p>
  <p>So I open that folder in VS Code, and open a source file out of the folder.
  The live error checker of VS Code underlines certain types. It can find them (Ctrl+Lclick), but they are marked as &quot;undefined&quot;. Presumably because it has no knowledge of those global defines, and hence none of the target-specific code is enabled by its compile switch.</p>
  <p>I found a SO question that was about adding defines to a <em>makefile</em> project, for building.
  That doesn't help here, I do <strong>not want to build</strong> with VS Code.
  I'd like the types be known to the VS Code <strong>'live' error checker</strong> and hence visual indicators of not-really-problems to disappear.</p>
  <p>Edit: And of course, auto-completion also does not work for the &quot;undefined&quot; types, which I'd like to fix, too.</p>
  <p>Is that possible / how?</p>