[clang] Silence spurious -Wnontrivial-memcall warnings in C mode (PR #137429)

[Oliver Hunt via cfe-commits]

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@@ -0,0 +1,42 @@
+// RUN: %clang_cc1 -triple arm64-apple-ios -fptrauth-calls -fptrauth-intrinsics -fsyntax-only -verify %s
+// RUN: %clang_cc1 -triple aarch64-linux-gnu -fptrauth-calls -fptrauth-intrinsics -fsyntax-only -verify %s
+
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ojhunt wrote:

Given there are c++ guards can we also have this test run with `-x c++` and ensure correct warnings? (might need to have a different `verify=cppexpected` if the diagnostics are significantly different

https://github.com/llvm/llvm-project/pull/137429