Auto merge of #30458 - fhahn:fix-warnings-tests-stdlib, r=sanxiyn

This PR siliences some warnings when compiling stdlib with --test. Mostly remove some unused imports and added a few `#[allow(..)]`.

I also marked some signal handling functions with `#[cfg(not(test))]`, because they are only called through `rt::lang_start`, which is also marked as  `#[cfg(not(test))]`

3 files changed, 9 insertions, 5 deletions

diff --git a/src/libstd/num/f32.rs b/src/libstd/num/f32.rs
index 30bee80fbf6..1cd258a5a72 100644
--- a/src/libstd/num/f32.rs
+++ b/src/libstd/num/f32.rs
@@ -15,11 +15,16 @@
 #![stable(feature = "rust1", since = "1.0.0")]
 #![allow(missing_docs)]
 
+#[cfg(not(test))]
 use core::num;
+#[cfg(not(test))]
 use intrinsics;
+#[cfg(not(test))]
 use libc::c_int;
+#[cfg(not(test))]
 use num::FpCategory;
 
+
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use core::f32::{RADIX, MANTISSA_DIGITS, DIGITS, EPSILON};
 #[stable(feature = "rust1", since = "1.0.0")]
diff --git a/src/libstd/num/f64.rs b/src/libstd/num/f64.rs
index d444b259445..b6a85ee0e9f 100644
--- a/src/libstd/num/f64.rs
+++ b/src/libstd/num/f64.rs
@@ -15,9 +15,13 @@
 #![stable(feature = "rust1", since = "1.0.0")]
 #![allow(missing_docs)]
 
+#[cfg(not(test))]
 use core::num;
+#[cfg(not(test))]
 use intrinsics;
+#[cfg(not(test))]
 use libc::c_int;
+#[cfg(not(test))]
 use num::FpCategory;
 
 #[stable(feature = "rust1", since = "1.0.0")]
diff --git a/src/libstd/num/mod.rs b/src/libstd/num/mod.rs
index 8e207f5e6cf..faaff494cab 100644
--- a/src/libstd/num/mod.rs
+++ b/src/libstd/num/mod.rs
@@ -47,11 +47,6 @@ pub fn test_num<T>(ten: T, two: T) where
 #[cfg(test)]
 mod tests {
     use super::*;
-    use i8;
-    use i16;
-    use i32;
-    use i64;
-    use isize;
     use u8;
     use u16;
     use u32;