[clang] [clang] Fix segmentation fault caused by stack overflow on deeply nested expressions (PR #111701)

[Ilya Biryukov via cfe-commits]

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@@ -0,0 +1,29 @@
+// RUN: %clang_cc1 %s -emit-llvm -o - -Wstack-exhausted
+
+class AClass {
+public:
+  AClass() {}
+  AClass &f() { return *this; }
+};
+
+#define CALLS1 f
+#define CALLS2 CALLS1().CALLS1
+#define CALLS4 CALLS2().CALLS2
+#define CALLS8 CALLS4().CALLS4
+#define CALLS16 CALLS8().CALLS8
+#define CALLS32 CALLS16().CALLS16
+#define CALLS64 CALLS32().CALLS32
+#define CALLS128 CALLS64().CALLS64
+#define CALLS256 CALLS128().CALLS128
+#define CALLS512 CALLS256().CALLS256
+#define CALLS1024 CALLS512().CALLS512
+#define CALLS2048 CALLS1024().CALLS1024
+#define CALLS4096 CALLS2048().CALLS2048
+#define CALLS8192 CALLS4096().CALLS4096
+#define CALLS16384 CALLS8192().CALLS8192
+#define CALLS32768 CALLS16384().CALLS16384
+
+void test_bar() {
+  AClass a;
+  a.CALLS32768();
+}
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ilya-biryukov wrote:

NIT: let's add a trailing newline to this file to make GitHub happy (it's also technically required by C++ standard, although I don't think any compiler actually cares in practice)

https://github.com/llvm/llvm-project/pull/111701