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

[Zahira Ammarguellat 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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zahiraam wrote:

This warning should trigger only for a division. When an `-fcomplex-arithmetic=promoted` is met, we don't have that knowledge. 

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