[clang] [clang] Implement CWG2627 Bit-fields and narrowing conversions (PR #78112)

[Aaron Ballman via cfe-commits]

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@@ -0,0 +1,44 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 %s
+// RUN: %clang_cc1 -triple x86_64-linux-pc -fsyntax-only -verify -std=c++11 %s
+// RUN: %clang_cc1 -triple x86_64-windows-pc -fsyntax-only -verify -std=c++11 %s
+// RUN: %clang_cc1 -triple i386-linux-pc -fsyntax-only -verify -std=c++11 %s
+// RUN: %clang_cc1 -triple i386-windows-pc -fsyntax-only -verify -std=c++11 %s
+
+#if __BITINT_MAXWIDTH__ >= 35
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AaronBallman wrote:

No need for this predicate, it's required to be at least the same width as `long long`.

https://github.com/llvm/llvm-project/pull/78112