[clang] [clang][bytecode] Fix crash on discarded complex comparison (PR #177731)

[Timm Baeder via cfe-commits]

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@@ -0,0 +1,16 @@
+// RUN: %clang_cc1 -std=c++20 -fsyntax-only -verify -fexperimental-new-constant-interpreter %s
+// RUN: %clang_cc1 -std=c++20 -fsyntax-only -verify %s
+
+// expected-no-diagnostics   
+
+void test_no_crash() {
+  _Complex int x = 1i;
+  (void)(x == 1i);
+}
+
+constexpr int test_side_effect() {
+  int k = 0;
+  (void)(1i == (++k, 1i));
+  return k;
+}
+static_assert(test_side_effect() == 1);
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tbaederr wrote:

Don't add a new file, you can just add this to an exisiting one.

https://github.com/llvm/llvm-project/pull/177731