[clang] [clang][Interp] IntegralAP zero-init (PR #68081)

[Timm Baeder via cfe-commits]

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@@ -100,12 +100,13 @@ template <bool Signed> class IntegralAP final {
   }
   static IntegralAP from(const Boolean &B) {
     assert(false);
-    return IntegralAP::zero();
+    return IntegralAP::zero(1);
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tbaederr wrote:

I don't have such comments because I opted for `assert(false)` where things are unimplemented :)

I keep opening smaller PRs _to make review easier_ because I thought that... makes it easier. If larger (but complete) patches are better for you, I can try to do that instead.

https://github.com/llvm/llvm-project/pull/68081