[clang] [clang] Fix crashes when initializing constexpr int* with floating-point (PR #180376)

[Mariya Podchishchaeva via cfe-commits]

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@@ -309,10 +309,10 @@ constexpr const int *V81 = &V80;
 constexpr int *V82 = 0;
 constexpr int *V83 = V82;
 constexpr int *V84 = 42;
-// expected-error at -1 {{constexpr variable 'V84' must be initialized by a constant expression}}
-// expected-note at -2 {{this conversion is not allowed in a constant expression}}
-// expected-error at -3 {{constexpr pointer initializer is not null}}
+// expected-error at -1 {{constexpr pointer initializer is not null}}
 constexpr int *V85 = nullptr;
+constexpr int *V91 = 0.0; 
+// expected-error at -1 {{constexpr pointer initializer is not null}}
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Fznamznon wrote:

This message sounds kind of confusing now.  For this one I think we should simply say that the types are not compatible.

https://github.com/llvm/llvm-project/pull/180376