1 files changed, 32 insertions, 0 deletions
diff --git a/pkgs/test/stdenv/gcc-stageCompare.nix b/pkgs/test/stdenv/gcc-stageCompare.nix
new file mode 100644
index 00000000000..e5c2ed5921b
--- /dev/null
+++ b/pkgs/test/stdenv/gcc-stageCompare.nix
@@ -0,0 +1,32 @@
+# This test *must* be run prior to releasing any build of either stdenv or the
+# gcc that it exports!  This check should also be part of CI for any PR that
+# causes a rebuild of `stdenv.cc`.
+#
+# When we used gcc's internal bootstrap it did this check as part of (and
+# serially with) the gcc derivation.  Now that we bootstrap externally this
+# check can be done in parallel with any/all of stdenv's referrers.  But we
+# must remember to do the check.
+#
+
+{ stdenv
+, pkgs
+, lib
+}:
+
+assert stdenv.cc.isGNU;
+with pkgs;
+# rebuild gcc using the "final" stdenv
+let gcc-stageCompare = (gcc-unwrapped.override {
+      reproducibleBuild = true;
+      profiledCompiler = false;
+      stdenv = overrideCC stdenv (wrapCCWith {
+        cc = stdenv.cc;
+      });
+    }).overrideAttrs(_: {
+      NIX_OUTPATH_USED_AS_RANDOM_SEED = stdenv.cc.cc.out;
+    });
+in (runCommand "gcc-stageCompare" {} ''
+  diff -sr ${pkgs.gcc-unwrapped.checksum}/checksums ${gcc-stageCompare.checksum}/checksums && touch $out
+'').overrideAttrs (a: {
+  meta = (a.meta or { }) // { platforms = lib.platforms.linux; };
+})