[clang] [C] Add -Wjump-bypasses-init (PR #138009)

[Aaron Ballman via cfe-commits]

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@@ -0,0 +1,31 @@
+// RUN: %clang_cc1 -fsyntax-only -verify=c,both -Wjump-bypasses-init %s
+// RUN: %clang_cc1 -fsyntax-only -verify=c,both -Wc++-compat %s
+// RUN: %clang_cc1 -fsyntax-only -verify=good %s
+// RUN: %clang_cc1 -fsyntax-only -verify=cxx,both -x c++ %s
+// good-no-diagnostics
+
+void goto_func_1(void) {
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AaronBallman wrote:

We currently accept those in C++ the same as GCC: https://godbolt.org/z/f4ze65vWT but I'm not convinced that's a good behavior. I think those *should* be rejected in C++. And I think this patch actually makes us start to reject them, so good call!

https://github.com/llvm/llvm-project/pull/138009