[clang] [clang][Interp] Zero-init remaining string literal elements (PR #66862)

[Shafik Yaghmour via cfe-commits]

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@@ -350,3 +350,22 @@ namespace ZeroInit {
   static_assert(b.f[0] == 0.0, "");
   static_assert(b.f[1] == 0.0, "");
 }
+
+namespace StringZeroFill {
+  struct A {
+    char c[12];
+  };
+  constexpr A a = { "abc" };
+  static_assert(a.c[0] == 'a', "");
+  static_assert(a.c[1] == 'b', "");
+  static_assert(a.c[2] == 'c', "");
+  static_assert(a.c[3] == '\0', "");
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shafik wrote:

Shouldn't we just test all the bytes? It is small enough.

https://github.com/llvm/llvm-project/pull/66862