diff --git a/debian/patches/series b/debian/patches/series
index 797c15920f..a2277b0c57 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -8,13 +8,14 @@ u-prefer-local-css.patch
 u-make-tests-work-without-rpath.patch
 u-tag-private-modules-with-doc-cfg.patch
 u-sparc64-cabi.patch
+u-rust-52760-test_loading_atoi.patch
+u-rust-52876-const-endianess.patch
 
 # https://github.com/rust-lang/compiler-rt/pull/35/
 u-compiler-rt.patch
 
 # Extra ignored tests. We now instead raise FAILURES_ALLOWED in d/rules but
 # these patches are kept in case they are useful for derivatives.
-#u-ignoretest-arm64_02.patch
 #u-ignoretest-ppc64el_02.patch
 
 # not forwarded, or forwarded but unlikely to be merged
diff --git a/debian/patches/u-ignoretest-arm64_02.patch b/debian/patches/u-ignoretest-arm64_02.patch
deleted file mode 100644
index e43f8299ca..0000000000
--- a/debian/patches/u-ignoretest-arm64_02.patch
+++ /dev/null
@@ -1,16 +0,0 @@
-Description: Don't run dynamic_lib::tests::test_loading_cosine on Aarch64 and
- powerpc64le whilst it fails.
-Author: Chris Coulson <chris.coulson@canonical.com>
-Bug: https://github.com/rust-lang/rust/issues/45410
-
---- a/src/librustc_metadata/dynamic_lib.rs
-+++ b/src/librustc_metadata/dynamic_lib.rs
-@@ -91,7 +91,7 @@
- 
-     #[test]
-     fn test_loading_cosine() {
--        if cfg!(windows) {
-+        if cfg!(any(windows, target_arch = "aarch64", all(target_arch = "powerpc64", target_endian = "little"))) {
-             return
-         }
- 
diff --git a/debian/patches/u-rust-52760-test_loading_atoi.patch b/debian/patches/u-rust-52760-test_loading_atoi.patch
new file mode 100644
index 0000000000..77ddf13db3
--- /dev/null
+++ b/debian/patches/u-rust-52760-test_loading_atoi.patch
@@ -0,0 +1,62 @@
+From efa11da26a882aaf57f7eae747e48d128c474bf3 Mon Sep 17 00:00:00 2001
+From: Josh Stone <jistone@redhat.com>
+Date: Thu, 26 Jul 2018 17:20:02 -0700
+Subject: [PATCH] rustc_metadata: test loading atoi instead of cos
+
+Some platforms don't actually have `libm` already linked in the test
+infrastructure, and then `dynamic_lib::tests::test_loading_cosine` would
+fail to find the "cos" symbol.  Every platform running this test should
+have `libc` and "atoi" though, so try to use that symbol instead.
+
+Fixes #45410.
+---
+ src/librustc_metadata/dynamic_lib.rs | 25 ++++++++++++-------------
+ 1 file changed, 12 insertions(+), 13 deletions(-)
+
+diff --git a/src/librustc_metadata/dynamic_lib.rs b/src/librustc_metadata/dynamic_lib.rs
+index d7da0d00012e..182a071277ec 100644
+--- a/src/librustc_metadata/dynamic_lib.rs
++++ b/src/librustc_metadata/dynamic_lib.rs
+@@ -90,30 +90,29 @@ mod tests {
+     use std::mem;
+ 
+     #[test]
+-    fn test_loading_cosine() {
++    fn test_loading_atoi() {
+         if cfg!(windows) {
+             return
+         }
+ 
+-        // The math library does not need to be loaded since it is already
+-        // statically linked in
+-        let libm = match DynamicLibrary::open(None) {
++        // The C library does not need to be loaded since it is already linked in
++        let lib = match DynamicLibrary::open(None) {
+             Err(error) => panic!("Could not load self as module: {}", error),
+-            Ok(libm) => libm
++            Ok(lib) => lib
+         };
+ 
+-        let cosine: extern fn(libc::c_double) -> libc::c_double = unsafe {
+-            match libm.symbol("cos") {
+-                Err(error) => panic!("Could not load function cos: {}", error),
+-                Ok(cosine) => mem::transmute::<*mut u8, _>(cosine)
++        let atoi: extern fn(*const libc::c_char) -> libc::c_int = unsafe {
++            match lib.symbol("atoi") {
++                Err(error) => panic!("Could not load function atoi: {}", error),
++                Ok(atoi) => mem::transmute::<*mut u8, _>(atoi)
+             }
+         };
+ 
+-        let argument = 0.0;
+-        let expected_result = 1.0;
+-        let result = cosine(argument);
++        let argument = CString::new("1383428980").unwrap();
++        let expected_result = 0x52757374;
++        let result = atoi(argument.as_ptr());
+         if result != expected_result {
+-            panic!("cos({}) != {} but equaled {} instead", argument,
++            panic!("atoi({:?}) != {} but equaled {} instead", argument,
+                    expected_result, result)
+         }
+     }
diff --git a/debian/patches/u-rust-52876-const-endianess.patch b/debian/patches/u-rust-52876-const-endianess.patch
new file mode 100644
index 0000000000..1e844e8274
--- /dev/null
+++ b/debian/patches/u-rust-52876-const-endianess.patch
@@ -0,0 +1,26 @@
+From 1ea2765918d1212a07e1359537470c477d82a681 Mon Sep 17 00:00:00 2001
+From: Josh Stone <jistone@redhat.com>
+Date: Mon, 30 Jul 2018 13:08:56 -0700
+Subject: [PATCH] run-pass/const-endianness: negate before to_le()
+
+`const LE_I128` needs parentheses to negate the value *before* calling
+`to_le()`, otherwise it doesn't match the operations performed in the
+black-boxed part of the test.  This only makes a tangible difference on
+big-endian targets.
+---
+ src/test/run-pass/const-endianess.rs | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/src/test/run-pass/const-endianess.rs b/src/test/run-pass/const-endianess.rs
+index fa34b49210a6..95c738d3ec49 100644
+--- a/src/test/run-pass/const-endianess.rs
++++ b/src/test/run-pass/const-endianess.rs
+@@ -25,7 +25,7 @@ fn main() {
+     #[cfg(not(target_arch = "asmjs"))]
+     {
+         const BE_U128: u128 = 999999u128.to_be();
+-        const LE_I128: i128 = -999999i128.to_le();
++        const LE_I128: i128 = (-999999i128).to_le();
+         assert_eq!(BE_U128, b(999999u128).to_be());
+         assert_eq!(LE_I128, b(-999999i128).to_le());
+     }