[clang] [Clang][Sema] Error message refers to `__begin1` with `constexpr` variable in range-based for loop (PR #218145)

[Akash Manna via cfe-commits]

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@@ -501,3 +501,11 @@ namespace SubPtr {
                                                      // both-note {{subtracted pointers are not elements of the same array}}
   constexpr auto diff8 = &a[1][2].n - (&a[1][2].n + 1);
 }
+
+namespace ConstexprForRangeVar {
+  void f() {
+    int arr[] = {1, 2, 3};
+    for (constexpr int a : arr) {} // both-error {{constexpr variable 'a' must be initialized by a constant expression}} \
+                                   // both-note {{range-based for loop variable is initialized on each iteration from the loop's iterator, whose value is not known at compile time}}
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akash-manna-sky wrote:

 dropped that framing; the note now names the begin variable instead.

https://github.com/llvm/llvm-project/pull/218145