[clang] [clang] Add __nullptr as a keyword to C (PR #123119)

[Erich Keane via cfe-commits]

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@@ -108,3 +108,8 @@ void test_f1() {
   int ir = (f1)(nullptr);
 }
 
+// __nullptr keyword in C
+void foo(void *);
+void bar() { foo(__nullptr); }
+static_assert(nullptr == __nullptr);
+static_assert(_Generic(typeof(__nullptr), nullptr_t: true, default: false));
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erichkeane wrote:

This isn't actually done here.  This test is C2x only, Aaron was asking for a C17 test as well.

https://github.com/llvm/llvm-project/pull/123119