From 5a71fa84478ae86d2306aba0e9c4d79d1970ecb5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Vladim=C3=ADr=20=C4=8Cun=C3=A1t?= <v@cunat.cz>
Date: Wed, 30 Jun 2021 19:47:13 +0200
Subject: [PATCH] stdenv bootstrap: hack around glibc version mismatch

With this we shouldn't need other workarounds for the LTO problems.
---
 pkgs/stdenv/linux/default.nix | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/pkgs/stdenv/linux/default.nix b/pkgs/stdenv/linux/default.nix
index 63a37d54547d..1fbd3cba27ef 100644
--- a/pkgs/stdenv/linux/default.nix
+++ b/pkgs/stdenv/linux/default.nix
@@ -258,6 +258,25 @@ in
         # Rewrap the binutils with the new glibc, so both the next
         # stage's wrappers use it.
         libc = getLibc self;
+
+        # Unfortunately, when building gcc in the next stage, its LTO plugin
+        # would use the final libc but `ld` would use the bootstrap one,
+        # and that can fail to load.  Therefore we upgrade `ld` to use newer libc;
+        # apparently the interpreter needs to match libc, too.
+        bintools = self.stdenvNoCC.mkDerivation {
+          inherit (prevStage.bintools.bintools) name;
+          dontUnpack = true;
+          dontBuild = true;
+          # We wouldn't need to *copy* all, but it's easier and the result is temporary anyway.
+          installPhase = ''
+            mkdir -p "$out"/bin
+            cp -a '${prevStage.bintools.bintools}'/bin/* "$out"/bin/
+            chmod +w "$out"/bin/ld.bfd
+            patchelf --set-interpreter '${getLibc self}'/lib/ld*.so.? \
+              --set-rpath "${getLibc self}/lib:$(patchelf --print-rpath "$out"/bin/ld.bfd)" \
+              "$out"/bin/ld.bfd
+          '';
+        };
       };
     };
   })