[clang] [llvm] [ARM] Emit an error when the hard-float ABI is enabled but can't be used. (PR #111334)

[Chris Copeland via cfe-commits]

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@@ -459,9 +459,6 @@ def warn_drv_assuming_mfloat_abi_is : Warning<
 def warn_drv_unsupported_float_abi_by_lib : Warning<
   "float ABI '%0' is not supported by current library">,
   InGroup<UnsupportedABI>;
-def warn_drv_no_floating_point_registers: Warning<
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chrisnc wrote:

`-Wunsupported-abi` still exists (it is a group containing several warnings). The only thing that is removed here is the particular manifestation of this warning for the ARM target. It should only be a build breakage if `-Wunsupported-abi` were removed completely.

https://github.com/llvm/llvm-project/pull/111334