[clang] [clang][Diagnostics] Add source range to uninitialized diagnostics (PR #65896)

[Takuya Shimizu via cfe-commits]

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@@ -4443,7 +4444,7 @@ struct CompoundAssignSubobjectHandler {
       return foundVector(Subobj, SubobjType);
     case APValue::Indeterminate:
       Info.FFDiag(E, diag::note_constexpr_access_uninit)
-          << /*read of=*/0 << /*uninitialized object=*/1;
+          << /*read of=*/0 << /*uninitialized object=*/1 << E->getSourceRange();
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hazohelet wrote:

I prefer `E->getLHS()->getSourceRange()` because the uninitialized object is known to exist in LHS.

https://github.com/llvm/llvm-project/pull/65896