[clang] [clang] Diagnose default arguments defined in different scopes (PR #124844)

[Vlad Serebrennikov via cfe-commits]

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@@ -27,3 +27,23 @@ extern double(*func2)(
   P_10000(int u)
   P_10000(int v) // expected-error {{too many function parameters; subsequent parameters will be ignored}}
   int w);
+
+#define PD_10(x) x, x, x, x, x, x, x, x, x, x,
+#define PD_100(x) PD_10(x) PD_10(x) PD_10(x) PD_10(x) PD_10(x) \
+                  PD_10(x) PD_10(x) PD_10(x) PD_10(x) PD_10(x)
+#define PD_1000(x) PD_100(x) PD_100(x) PD_100(x) PD_100(x) PD_100(x) \
+                   PD_100(x) PD_100(x) PD_100(x) PD_100(x) PD_100(x)
+#define PD_10000(x) PD_1000(x) PD_1000(x) PD_1000(x) PD_1000(x) PD_1000(x) \
+                    PD_1000(x) PD_1000(x) PD_1000(x) PD_1000(x) PD_1000(x)
+
+extern "C" int func3( 
+  PD_10000(int = 0)
+  PD_10000(int = 0)
+  PD_10000(int = 0)
+  PD_10000(int = 0)
+  PD_10000(int = 0)
+  PD_10000(int = 0)
+  PD_10000(int = 0) // expected-error {{too many function parameters; subsequent parameters will be ignored}} 
+  int = 0);
+
+int h = func3();
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Endilll wrote:

It was intended as a test for the code that emits diagnostics, but I need to update it, yeah.

https://github.com/llvm/llvm-project/pull/124844