Remove legacy integer methods

diff --git a/bindgen/clang.rs b/bindgen/clang.rs
index 4d79390..0dcd538 100644
--- a/bindgen/clang.rs
+++ b/bindgen/clang.rs

@@ -2356,7 +2356,7 @@
 
         if unsafe { clang_EvalResult_isUnsignedInt(self.x) } != 0 {
             let value = unsafe { clang_EvalResult_getAsUnsigned(self.x) };
-            if value > i64::max_value() as c_ulonglong {
+            if value > i64::MAX as c_ulonglong {
                 return None;
             }
 
@@ -2364,10 +2364,10 @@
         }
 
         let value = unsafe { clang_EvalResult_getAsLongLong(self.x) };
-        if value > i64::max_value() as c_longlong {
+        if value > i64::MAX as c_longlong {
             return None;
         }
-        if value < i64::min_value() as c_longlong {
+        if value < i64::MIN as c_longlong {
             return None;
         }
         #[allow(clippy::unnecessary_cast)]

diff --git a/bindgen/ir/var.rs b/bindgen/ir/var.rs
index a970cf1..9d46135 100644
--- a/bindgen/ir/var.rs
+++ b/bindgen/ir/var.rs

@@ -129,27 +129,23 @@
         ctx.options().default_macro_constant_type ==
             MacroTypeVariation::Signed
     {
-        if value < i32::min_value() as i64 || value > i32::max_value() as i64 {
+        if value < i32::MIN as i64 || value > i32::MAX as i64 {
             IntKind::I64
         } else if !ctx.options().fit_macro_constants ||
-            value < i16::min_value() as i64 ||
-            value > i16::max_value() as i64
+            value < i16::MIN as i64 ||
+            value > i16::MAX as i64
         {
             IntKind::I32
-        } else if value < i8::min_value() as i64 ||
-            value > i8::max_value() as i64
-        {
+        } else if value < i8::MIN as i64 || value > i8::MAX as i64 {
             IntKind::I16
         } else {
             IntKind::I8
         }
-    } else if value > u32::max_value() as i64 {
+    } else if value > u32::MAX as i64 {
         IntKind::U64
-    } else if !ctx.options().fit_macro_constants ||
-        value > u16::max_value() as i64
-    {
+    } else if !ctx.options().fit_macro_constants || value > u16::MAX as i64 {
         IntKind::U32
-    } else if value > u8::max_value() as i64 {
+    } else if value > u8::MAX as i64 {
         IntKind::U16
     } else {
         IntKind::U8
@@ -243,7 +239,7 @@
                                 c as u8
                             }
                             CChar::Raw(c) => {
-                                assert!(c <= ::std::u8::MAX as u64);
+                                assert!(c <= u8::MAX as u64);
                                 c as u8
                             }
                         };