From b4f66903e3d55fd32061b790ad3080b0c963a5fb Mon Sep 17 00:00:00 2001
From: sternenseemann <0rpkxez4ksa01gb3typccl0i@systemli.org>
Date: Tue, 24 Aug 2021 00:57:19 +0200
Subject: [PATCH] haskell.compiler.*: make big-parallel

Compiling GHC on Hydra takes 3h or more (with -j2) whereas even on an
outdated CPU GHC can be compiled in under an hour with -j4. To get a
higher NIX_BUILD_CORES value at build time, we'll have to mark GHC
big-parallel.
---
 pkgs/development/compilers/ghc/8.10.6.nix | 4 ++++
 pkgs/development/compilers/ghc/8.8.4.nix  | 4 ++++
 pkgs/development/compilers/ghc/9.0.1.nix  | 4 ++++
 pkgs/development/compilers/ghc/9.2.1.nix  | 4 ++++
 pkgs/development/compilers/ghc/head.nix   | 4 ++++
 5 files changed, 20 insertions(+)

diff --git a/pkgs/development/compilers/ghc/8.10.6.nix b/pkgs/development/compilers/ghc/8.10.6.nix
index 859c23a796b7..748116afb105 100644
--- a/pkgs/development/compilers/ghc/8.10.6.nix
+++ b/pkgs/development/compilers/ghc/8.10.6.nix
@@ -281,6 +281,10 @@ stdenv.mkDerivation (rec {
     # * https://gitlab.haskell.org/ghc/ghc/-/issues/19580
     ++ lib.optional stdenv.targetPlatform.isMusl "pie";
 
+  # big-parallel allows us to build with more than 2 cores on
+  # Hydra which already warrants a significant speedup
+  requiredSystemFeatures = [ "big-parallel" ];
+
   postInstall = ''
     # Install the bash completion file.
     install -D -m 444 utils/completion/ghc.bash $out/share/bash-completion/completions/${targetPrefix}ghc
diff --git a/pkgs/development/compilers/ghc/8.8.4.nix b/pkgs/development/compilers/ghc/8.8.4.nix
index 66862fca7318..bb47b1daee47 100644
--- a/pkgs/development/compilers/ghc/8.8.4.nix
+++ b/pkgs/development/compilers/ghc/8.8.4.nix
@@ -291,6 +291,10 @@ stdenv.mkDerivation (rec {
     # * https://gitlab.haskell.org/ghc/ghc/-/issues/19580
     ++ lib.optional stdenv.targetPlatform.isMusl "pie";
 
+  # big-parallel allows us to build with more than 2 cores on
+  # Hydra which already warrants a significant speedup
+  requiredSystemFeatures = [ "big-parallel" ];
+
   postInstall = ''
     # Install the bash completion file.
     install -D -m 444 utils/completion/ghc.bash $out/share/bash-completion/completions/${targetPrefix}ghc
diff --git a/pkgs/development/compilers/ghc/9.0.1.nix b/pkgs/development/compilers/ghc/9.0.1.nix
index bf94fc3c4d00..c2cc1358e821 100644
--- a/pkgs/development/compilers/ghc/9.0.1.nix
+++ b/pkgs/development/compilers/ghc/9.0.1.nix
@@ -268,6 +268,10 @@ stdenv.mkDerivation (rec {
     # * https://gitlab.haskell.org/ghc/ghc/-/issues/19580
     ++ lib.optional stdenv.targetPlatform.isMusl "pie";
 
+  # big-parallel allows us to build with more than 2 cores on
+  # Hydra which already warrants a significant speedup
+  requiredSystemFeatures = [ "big-parallel" ];
+
   postInstall = ''
     # Install the bash completion file.
     install -D -m 444 utils/completion/ghc.bash $out/share/bash-completion/completions/${targetPrefix}ghc
diff --git a/pkgs/development/compilers/ghc/9.2.1.nix b/pkgs/development/compilers/ghc/9.2.1.nix
index c77fde7f06e9..46bacd5df1a8 100644
--- a/pkgs/development/compilers/ghc/9.2.1.nix
+++ b/pkgs/development/compilers/ghc/9.2.1.nix
@@ -268,6 +268,10 @@ stdenv.mkDerivation (rec {
     # * https://gitlab.haskell.org/ghc/ghc/-/issues/19580
     ++ lib.optional stdenv.targetPlatform.isMusl "pie";
 
+  # big-parallel allows us to build with more than 2 cores on
+  # Hydra which already warrants a significant speedup
+  requiredSystemFeatures = [ "big-parallel" ];
+
   postInstall = ''
     # Install the bash completion file.
     install -D -m 444 utils/completion/ghc.bash $out/share/bash-completion/completions/${targetPrefix}ghc
diff --git a/pkgs/development/compilers/ghc/head.nix b/pkgs/development/compilers/ghc/head.nix
index 6b7d7c21e491..6eefc067d6e8 100644
--- a/pkgs/development/compilers/ghc/head.nix
+++ b/pkgs/development/compilers/ghc/head.nix
@@ -285,6 +285,10 @@ stdenv.mkDerivation (rec {
     # * https://gitlab.haskell.org/ghc/ghc/-/issues/19580
     ++ lib.optional stdenv.targetPlatform.isMusl "pie";
 
+  # big-parallel allows us to build with more than 2 cores on
+  # Hydra which already warrants a significant speedup
+  requiredSystemFeatures = [ "big-parallel" ];
+
   postInstall = ''
     # Install the bash completion file.
     install -D -m 444 utils/completion/ghc.bash $out/share/bash-completion/completions/${targetPrefix}ghc