[clang] [Driver] Print C++ standard library info (PR #207798)

[Artem Belevich via cfe-commits]

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@@ -136,6 +136,40 @@ template <typename F> static bool usesInput(const ArgList &Args, F &&Fn) {
   });
 }
 
+static StringRef getCXXStdlibName(const ToolChain &TC, const ArgList &Args) {
+  if (TC.getTriple().isWindowsMSVCEnvironment() &&
+      !Args.hasArg(options::OPT_stdlib_EQ))
+    return "msvcstl";
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Artem-B wrote:

This should probably come from wherever we may actually set/use it as the default. This is not a good place to guess some platform's default.

https://github.com/llvm/llvm-project/pull/207798