[clang] [NFC] Move warning from CodeGen to Sema. (PR #107397)

[Eli Friedman via cfe-commits]

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@@ -6784,6 +6784,10 @@ def warn_arc_lifetime_result_type : Warning<
   "ARC %select{unused|__unsafe_unretained|__strong|__weak|__autoreleasing}0 "
   "lifetime qualifier on return type is ignored">,
   InGroup<IgnoredQualifiers>;
+def warn_next_larger_fp_type_same_size_than_fp : Warning<
+  "higher precision floating-point type requested by user size has the same size"
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efriedma-quic wrote:

This warning doesn't make sense to me.  Ignoring the weird grammar, the user didn't choose the higher precision type. The compiler chooses how it does the computation.

If the issue here that the target doesn't support a higher precision floating-point type, we should just say that.

https://github.com/llvm/llvm-project/pull/107397