4 files changed, 39 insertions, 0 deletions
diff --git a/pkgs/development/compilers/go/1.9.nix b/pkgs/development/compilers/go/1.9.nix
index b8660008d941..007b81d995b7 100644
--- a/pkgs/development/compilers/go/1.9.nix
+++ b/pkgs/development/compilers/go/1.9.nix
@@ -119,6 +119,7 @@ stdenv.mkDerivation rec {
       ./creds-test.patch
       ./remove-test-pie-1.9.patch
       ./go-1.9-skip-flaky-19608.patch
+      ./go-1.9-skip-flaky-20072.patch
     ];
 
   postPatch = optionalString stdenv.isDarwin ''
diff --git a/pkgs/development/compilers/go/go-1.9-skip-flaky-20072.patch b/pkgs/development/compilers/go/go-1.9-skip-flaky-20072.patch
new file mode 100644
index 000000000000..13db40ababc3
--- /dev/null
+++ b/pkgs/development/compilers/go/go-1.9-skip-flaky-20072.patch
@@ -0,0 +1,20 @@
+diff --git a/src/sync/waitgroup_test.go b/src/sync/waitgroup_test.go
+index e3e3096..f80d1e2 100644
+--- a/src/sync/waitgroup_test.go
++++ b/src/sync/waitgroup_test.go
+@@ -6,6 +6,7 @@ package sync_test
+ 
+ import (
+ 	"internal/race"
++	"internal/testenv"
+ 	"runtime"
+ 	. "sync"
+ 	"sync/atomic"
+@@ -73,6 +74,7 @@ func TestWaitGroupMisuse2(t *testing.T) {
+ 	if runtime.NumCPU() <= 4 {
+ 		t.Skip("NumCPU<=4, skipping: this test requires parallelism")
+ 	}
++	testenv.SkipFlaky(t, 20072)
+ 	defer func() {
+ 		err := recover()
+ 		if err != "sync: negative WaitGroup counter" &&
diff --git a/pkgs/development/compilers/mono/4.8.nix b/pkgs/development/compilers/mono/4.8.nix
new file mode 100644
index 000000000000..6d870ae30680
--- /dev/null
+++ b/pkgs/development/compilers/mono/4.8.nix
@@ -0,0 +1,7 @@
+{ stdenv, callPackage, Foundation, libobjc }:
+
+callPackage ./generic-cmake.nix (rec {
+  inherit Foundation libobjc;
+  version = "4.8.1.0";
+  sha256 = "1vyvp2g28ihcgxgxr8nhzyzdmzicsh5djzk8dk1hj5p5f2k3ijqq";
+})
diff --git a/pkgs/development/compilers/rust/rust-src.nix b/pkgs/development/compilers/rust/rust-src.nix
new file mode 100644
index 000000000000..1b819a7f6068
--- /dev/null
+++ b/pkgs/development/compilers/rust/rust-src.nix
@@ -0,0 +1,11 @@
+{ stdenv, rustc }:
+
+stdenv.mkDerivation {
+  name = "rust-src";
+  src = rustc.src;
+  phases = [ "unpackPhase" "installPhase" ];
+  installPhase = ''
+    mv src $out
+    rm -rf $out/{ci,doc,driver,etc,grammar,llvm,rt,rtstartup,rustllvm,test,tools,vendor}
+  '';
+}