[clang] [CIR] Add Support For Library Builtins (PR #143984)

[Morris Hafner via cfe-commits]

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@@ -76,3 +76,21 @@ float constant_fp_builtin_single() {
 // OGCG: define {{.*}}float @_Z26constant_fp_builtin_singlev()
 // OGCG: ret float 0x3FB99999A0000000
 // OGCG: }
+
+void library_builtins() {
+  __builtin_printf(nullptr);
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mmha wrote:

I added `builtin_printf.cpp` that contains a few `printf` calls

https://github.com/llvm/llvm-project/pull/143984