[gn build] add a FIXME about using /Gw on win

diff --git a/llvm/utils/gn/build/BUILD.gn b/llvm/utils/gn/build/BUILD.gn
index b06ef9a..7947a36 100644 (file)
--- a/llvm/utils/gn/build/BUILD.gn
+++ b/llvm/utils/gn/build/BUILD.gn
@@ -59,6 +59,7 @@ config("compiler_defaults") {
     }
     if (is_optimized) {
       cflags += [
+        # FIXME: evaluate /Gw (not part of /O2)
         "/O2",
         "/Zc:inline",
       ]