constify parts of libcore.

6 files changed, 20 insertions, 22 deletions

diff --git a/src/libcore/num/dec2flt/mod.rs b/src/libcore/num/dec2flt/mod.rs
index f93564c2849..0e1f6664d96 100644
--- a/src/libcore/num/dec2flt/mod.rs
+++ b/src/libcore/num/dec2flt/mod.rs
@@ -187,11 +187,11 @@ impl fmt::Display for ParseFloatError {
     }
 }
 
-fn pfe_empty() -> ParseFloatError {
+const fn pfe_empty() -> ParseFloatError {
     ParseFloatError { kind: FloatErrorKind::Empty }
 }
 
-fn pfe_invalid() -> ParseFloatError {
+const fn pfe_invalid() -> ParseFloatError {
     ParseFloatError { kind: FloatErrorKind::Invalid }
 }
 
diff --git a/src/libcore/num/dec2flt/parse.rs b/src/libcore/num/dec2flt/parse.rs
index e7ed94d4d91..8d8f357425e 100644
--- a/src/libcore/num/dec2flt/parse.rs
+++ b/src/libcore/num/dec2flt/parse.rs
@@ -39,7 +39,7 @@ pub struct Decimal<'a> {
 }
 
 impl<'a> Decimal<'a> {
-    pub fn new(integral: &'a [u8], fractional: &'a [u8], exp: i64) -> Decimal<'a> {
+    pub const fn new(integral: &'a [u8], fractional: &'a [u8], exp: i64) -> Decimal<'a> {
         Decimal { integral, fractional, exp }
     }
 }
diff --git a/src/libcore/num/dec2flt/rawfp.rs b/src/libcore/num/dec2flt/rawfp.rs
index 38f4e4687a9..c5d4aa68958 100644
--- a/src/libcore/num/dec2flt/rawfp.rs
+++ b/src/libcore/num/dec2flt/rawfp.rs
@@ -44,7 +44,7 @@ pub struct Unpacked {
 }
 
 impl Unpacked {
-    pub fn new(sig: u64, k: i16) -> Self {
+    pub const fn new(sig: u64, k: i16) -> Self {
         Unpacked { sig, k }
     }
 }
diff --git a/src/libcore/num/flt2dec/estimator.rs b/src/libcore/num/flt2dec/estimator.rs
index d42e05a91f1..2a87bf43664 100644
--- a/src/libcore/num/flt2dec/estimator.rs
+++ b/src/libcore/num/flt2dec/estimator.rs
@@ -15,11 +15,10 @@
 /// This is used to approximate `k = ceil(log_10 (mant * 2^exp))`;
 /// the true `k` is either `k_0` or `k_0+1`.
 #[doc(hidden)]
-pub fn estimate_scaling_factor(mant: u64, exp: i16) -> i16 {
+pub const fn estimate_scaling_factor(mant: u64, exp: i16) -> i16 {
     // 2^(nbits-1) < mant <= 2^nbits if mant > 0
     let nbits = 64 - (mant - 1).leading_zeros() as i64;
     // 1292913986 = floor(2^32 * log_10 2)
     // therefore this always underestimates (or is exact), but not much.
     (((nbits + exp as i64) * 1292913986) >> 32) as i16
 }
-
diff --git a/src/libcore/num/flt2dec/mod.rs b/src/libcore/num/flt2dec/mod.rs
index 21a2e72dac8..d58015beecb 100644
--- a/src/libcore/num/flt2dec/mod.rs
+++ b/src/libcore/num/flt2dec/mod.rs
@@ -658,4 +658,3 @@ pub fn to_exact_fixed_str<'a, T, F>(mut format_exact: F, v: T,
         }
     }
 }
-
diff --git a/src/libcore/num/wrapping.rs b/src/libcore/num/wrapping.rs
index 1c826c2fa76..00134a58d30 100644
--- a/src/libcore/num/wrapping.rs
+++ b/src/libcore/num/wrapping.rs
@@ -387,7 +387,7 @@ assert_eq!(n.count_ones(), 3);
 ```"),
                 #[inline]
                 #[unstable(feature = "wrapping_int_impl", issue = "32463")]
-                pub fn count_ones(self) -> u32 {
+                pub const fn count_ones(self) -> u32 {
                     self.0.count_ones()
                 }
             }
@@ -407,7 +407,7 @@ assert_eq!(Wrapping(!0", stringify!($t), ").count_zeros(), 0);
 ```"),
                 #[inline]
                 #[unstable(feature = "wrapping_int_impl", issue = "32463")]
-                pub fn count_zeros(self) -> u32 {
+                pub const fn count_zeros(self) -> u32 {
                     self.0.count_zeros()
                 }
             }
@@ -430,7 +430,7 @@ assert_eq!(n.trailing_zeros(), 3);
 ```"),
                 #[inline]
                 #[unstable(feature = "wrapping_int_impl", issue = "32463")]
-                pub fn trailing_zeros(self) -> u32 {
+                pub const fn trailing_zeros(self) -> u32 {
                     self.0.trailing_zeros()
                 }
             }
@@ -456,7 +456,7 @@ assert_eq!(n.trailing_zeros(), 3);
             /// ```
             #[inline]
             #[unstable(feature = "wrapping_int_impl", issue = "32463")]
-            pub fn rotate_left(self, n: u32) -> Self {
+            pub const fn rotate_left(self, n: u32) -> Self {
                 Wrapping(self.0.rotate_left(n))
             }
 
@@ -481,7 +481,7 @@ assert_eq!(n.trailing_zeros(), 3);
             /// ```
             #[inline]
             #[unstable(feature = "wrapping_int_impl", issue = "32463")]
-            pub fn rotate_right(self, n: u32) -> Self {
+            pub const fn rotate_right(self, n: u32) -> Self {
                 Wrapping(self.0.rotate_right(n))
             }
 
@@ -505,7 +505,7 @@ assert_eq!(n.trailing_zeros(), 3);
             /// ```
             #[inline]
             #[unstable(feature = "wrapping_int_impl", issue = "32463")]
-            pub fn swap_bytes(self) -> Self {
+            pub const fn swap_bytes(self) -> Self {
                 Wrapping(self.0.swap_bytes())
             }
 
@@ -532,7 +532,7 @@ assert_eq!(n.trailing_zeros(), 3);
             /// ```
             #[unstable(feature = "reverse_bits", issue = "48763")]
             #[inline]
-            pub fn reverse_bits(self) -> Self {
+            pub const fn reverse_bits(self) -> Self {
                 Wrapping(self.0.reverse_bits())
             }
 
@@ -560,7 +560,7 @@ if cfg!(target_endian = \"big\") {
 ```"),
                 #[inline]
                 #[unstable(feature = "wrapping_int_impl", issue = "32463")]
-                pub fn from_be(x: Self) -> Self {
+                pub const fn from_be(x: Self) -> Self {
                     Wrapping(<$t>::from_be(x.0))
                 }
             }
@@ -589,7 +589,7 @@ if cfg!(target_endian = \"little\") {
 ```"),
                 #[inline]
                 #[unstable(feature = "wrapping_int_impl", issue = "32463")]
-                pub fn from_le(x: Self) -> Self {
+                pub const fn from_le(x: Self) -> Self {
                     Wrapping(<$t>::from_le(x.0))
                 }
             }
@@ -618,7 +618,7 @@ if cfg!(target_endian = \"big\") {
 ```"),
                 #[inline]
                 #[unstable(feature = "wrapping_int_impl", issue = "32463")]
-                pub fn to_be(self) -> Self {
+                pub const fn to_be(self) -> Self {
                     Wrapping(self.0.to_be())
                 }
             }
@@ -647,7 +647,7 @@ if cfg!(target_endian = \"little\") {
 ```"),
                 #[inline]
                 #[unstable(feature = "wrapping_int_impl", issue = "32463")]
-                pub fn to_le(self) -> Self {
+                pub const fn to_le(self) -> Self {
                     Wrapping(self.0.to_le())
                 }
             }
@@ -707,7 +707,7 @@ assert_eq!(n.leading_zeros(), 3);
 ```"),
                 #[inline]
                 #[unstable(feature = "wrapping_int_impl", issue = "32463")]
-                pub fn leading_zeros(self) -> u32 {
+                pub const fn leading_zeros(self) -> u32 {
                     self.0.leading_zeros()
                 }
             }
@@ -784,7 +784,7 @@ assert!(!Wrapping(-10", stringify!($t), ").is_positive());
 ```"),
                 #[inline]
                 #[unstable(feature = "wrapping_int_impl", issue = "32463")]
-                pub fn is_positive(self) -> bool {
+                pub const fn is_positive(self) -> bool {
                     self.0.is_positive()
                 }
             }
@@ -806,7 +806,7 @@ assert!(!Wrapping(10", stringify!($t), ").is_negative());
 ```"),
                 #[inline]
                 #[unstable(feature = "wrapping_int_impl", issue = "32463")]
-                pub fn is_negative(self) -> bool {
+                pub const fn is_negative(self) -> bool {
                     self.0.is_negative()
                 }
             }
@@ -836,7 +836,7 @@ assert_eq!(n.leading_zeros(), 2);
 ```"),
                 #[inline]
                 #[unstable(feature = "wrapping_int_impl", issue = "32463")]
-                pub fn leading_zeros(self) -> u32 {
+                pub const fn leading_zeros(self) -> u32 {
                     self.0.leading_zeros()
                 }
             }