Auto merge of #142723 - beetrees:crater-impl-from-f16-for-f32, r=<try>

[crater] Add `impl From<f16> for f32`

Crater run to see what the effects of adding `impl From<f16> for f32` without changing the fallback (a.k.a. things that would be caught by the FCW in #139087). This needs a ``@craterbot` check`.

Author: rust-bors[bot]

library/core/src/convert/num.rs

@@ -184,8 +184,7 @@ impl_from!(u32 => f128, #[stable(feature = "lossless_float_conv", since = "1.6.0
 // impl_from!(u64 => f128, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
 
 // float -> float
-// FIXME(f16_f128): adding additional `From<{float}>` impls to `f32` breaks inference. See
-// <https://github.com/rust-lang/rust/issues/123831>
+impl_from!(f16 => f32, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
 impl_from!(f16 => f64, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
 impl_from!(f16 => f128, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
 impl_from!(f32 => f64, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);