diff --git a/src/etc/test-float-parse/src/lib.rs b/src/etc/test-float-parse/src/lib.rs
index 0bd4878f9a626..f590149523bd7 100644
--- a/src/etc/test-float-parse/src/lib.rs
+++ b/src/etc/test-float-parse/src/lib.rs
@@ -119,6 +119,7 @@ pub fn register_tests(cfg: &Config) -> Vec<TestInfo> {
 
     // Register normal generators for all floats.
 
+    #[cfg(not(bootstrap))]
     #[cfg(target_has_reliable_f16)]
     register_float::<f16>(&mut tests, cfg);
     register_float::<f32>(&mut tests, cfg);
diff --git a/src/etc/test-float-parse/src/traits.rs b/src/etc/test-float-parse/src/traits.rs
index 65a8721bfa5cd..16484f8fe2c23 100644
--- a/src/etc/test-float-parse/src/traits.rs
+++ b/src/etc/test-float-parse/src/traits.rs
@@ -170,6 +170,7 @@ macro_rules! impl_float {
 
 impl_float!(f32, u32; f64, u64);
 
+#[cfg(not(bootstrap))]
 #[cfg(target_has_reliable_f16)]
 impl_float!(f16, u16);