diff --git a/src/librustc_trans/trans/tvec.rs b/src/librustc_trans/trans/tvec.rs
index 791b58d88a9..b02fcb6cf0c 100644
--- a/src/librustc_trans/trans/tvec.rs
+++ b/src/librustc_trans/trans/tvec.rs
@@ -361,7 +361,7 @@ fn iter_vec_loop<'blk, 'tcx, F>(bcx: Block<'blk, 'tcx>,
         InBoundsGEP(bcx, data_ptr, &[loop_counter])
     };
     let bcx = f(bcx, lleltptr, vt.unit_ty);
-    let plusone = Add(bcx, loop_counter, C_uint(bcx.ccx(), 1us), DebugLoc::None);
+    let plusone = Add(bcx, loop_counter, C_uint(bcx.ccx(), 1usize), DebugLoc::None);
     AddIncomingToPhi(loop_counter, plusone, bcx.llbb);
 
     let cond_val = ICmp(bcx, llvm::IntULT, plusone, count, DebugLoc::None);
diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs
index 226e2037b2f..4b7b7b66582 100644
--- a/src/libsyntax/parse/mod.rs
+++ b/src/libsyntax/parse/mod.rs
@@ -714,8 +714,6 @@ pub fn integer_lit(s: &str, suffix: Option<&str>, sd: &SpanHandler, sp: Span) ->
             "u16" => ast::UnsignedIntLit(ast::TyU16),
             "u32" => ast::UnsignedIntLit(ast::TyU32),
             "u64" => ast::UnsignedIntLit(ast::TyU64),
-            "is" => ast::SignedIntLit(ast::TyIs, ast::Plus),
-            "us" => ast::UnsignedIntLit(ast::TyUs),
             _ => {
                 // i<digits> and u<digits> look like widths, so lets
                 // give an error message along those lines
diff --git a/src/test/auxiliary/issue-11224.rs b/src/test/auxiliary/issue-11224.rs
index 21935b6b9ab..15b72b37781 100644
--- a/src/test/auxiliary/issue-11224.rs
+++ b/src/test/auxiliary/issue-11224.rs
@@ -21,6 +21,6 @@ mod inner {
 }
 
 pub fn foo() {
-    let a = &1is as &inner::Trait;
+    let a = &1isize as &inner::Trait;
     a.f();
 }
diff --git a/src/test/compile-fail/lint-type-limits.rs b/src/test/compile-fail/lint-type-limits.rs
index 798dc112b0a..42515e0f00c 100644
--- a/src/test/compile-fail/lint-type-limits.rs
+++ b/src/test/compile-fail/lint-type-limits.rs
@@ -52,12 +52,12 @@ fn qux() {
 }
 
 fn quy() {
-    let i = -23_us; //~ WARNING negation of unsigned int literal may be unintentional
+    let i = -23_usize; //~ WARNING negation of unsigned int literal may be unintentional
                   //~^ WARNING unused variable
 }
 
 fn quz() {
-    let i = 23_us;
+    let i = 23_usize;
     let j = -i;   //~ WARNING negation of unsigned int variable may be unintentional
                   //~^ WARNING unused variable
 }
diff --git a/src/test/compile-fail/old-suffixes-are-really-forbidden.rs b/src/test/compile-fail/old-suffixes-are-really-forbidden.rs
new file mode 100644
index 00000000000..b18741d3932
--- /dev/null
+++ b/src/test/compile-fail/old-suffixes-are-really-forbidden.rs
@@ -0,0 +1,14 @@
+// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+fn main() {
+    let a = 1_is; //~ ERROR illegal suffix
+    let b = 2_us; //~ ERROR illegal suffix
+}
diff --git a/src/test/run-make/symbols-are-reasonable/lib.rs b/src/test/run-make/symbols-are-reasonable/lib.rs
index 8ba705bfb61..ff56ed62869 100644
--- a/src/test/run-make/symbols-are-reasonable/lib.rs
+++ b/src/test/run-make/symbols-are-reasonable/lib.rs
@@ -16,5 +16,5 @@ impl Foo for usize {}
 
 pub fn dummy() {
     // force the vtable to be created
-    let _x = &1us as &Foo;
+    let _x = &1usize as &Foo;
 }
diff --git a/src/test/run-pass/autoderef-method-on-trait.rs b/src/test/run-pass/autoderef-method-on-trait.rs
index 582fd020dd0..40acb6eb9fe 100644
--- a/src/test/run-pass/autoderef-method-on-trait.rs
+++ b/src/test/run-pass/autoderef-method-on-trait.rs
@@ -21,6 +21,6 @@ impl double for usize {
 }
 
 pub fn main() {
-    let x: Box<_> = box() (box 3us as Box<double>);
+    let x: Box<_> = box() (box 3usize as Box<double>);
     assert_eq!(x.double(), 6);
 }
diff --git a/src/test/run-pass/issue-15763.rs b/src/test/run-pass/issue-15763.rs
index b5251d63ff0..0baaaac2676 100644
--- a/src/test/run-pass/issue-15763.rs
+++ b/src/test/run-pass/issue-15763.rs
@@ -87,12 +87,12 @@ fn main() {
     assert_eq!(cc().unwrap(), 3);
     assert_eq!(dd().unwrap(), 3);
 
-    let i = box 32is as Box<A>;
+    let i = box 32isize as Box<A>;
     assert_eq!(i.aaa(), 3);
-    let i = box 32is as Box<A>;
+    let i = box 32isize as Box<A>;
     assert_eq!(i.bbb(), 3);
-    let i = box 32is as Box<A>;
+    let i = box 32isize as Box<A>;
     assert_eq!(i.ccc().unwrap(), 3);
-    let i = box 32is as Box<A>;
+    let i = box 32isize as Box<A>;
     assert_eq!(i.ddd().unwrap(), 3);
 }