From 89deec56234511babe7478a44f684afcec83b394 Mon Sep 17 00:00:00 2001
From: Bernardo Meurer <bernardo@meurer.org>
Date: Sun, 11 Jul 2021 21:55:40 -0700
Subject: buildLinux: apply hostPlatform.linux-kernel.makeFlags to
 generate-config.pl

This enforces that the configuration generated will obey any/all flags
set in the platform/stdenv configuration. This is crucial, for example,
if you'd like to build a kernel using clang.

Without this patch, anything you set in
`stdenv.hostPlatform.linux-kernel.makeFlags` is wholly ignored during
config generation, causing (for example) any changes in the desired
toolchain (e.g. `LLVM`, `LLVM_IAS`) to not be reflected in the generated
config, and for the subsequent build to fail.
---
 pkgs/os-specific/linux/kernel/generate-config.pl | 3 ++-
 pkgs/os-specific/linux/kernel/generic.nix        | 8 ++++++--
 2 files changed, 8 insertions(+), 3 deletions(-)

(limited to 'pkgs/os-specific/linux/kernel')

diff --git a/pkgs/os-specific/linux/kernel/generate-config.pl b/pkgs/os-specific/linux/kernel/generate-config.pl
index 82e1cb66e2be4..df807188f14f9 100644
--- a/pkgs/os-specific/linux/kernel/generate-config.pl
+++ b/pkgs/os-specific/linux/kernel/generate-config.pl
@@ -19,6 +19,7 @@ my $autoModules = $ENV{'AUTO_MODULES'};
 my $preferBuiltin = $ENV{'PREFER_BUILTIN'};
 my $ignoreConfigErrors = $ENV{'ignoreConfigErrors'};
 my $buildRoot = $ENV{'BUILD_ROOT'};
+my $makeFlags = $ENV{'MAKE_FLAGS'};
 $SIG{PIPE} = 'IGNORE';
 
 # Read the answers.
@@ -40,7 +41,7 @@ close ANSWERS;
 sub runConfig {
 
     # Run `make config'.
-    my $pid = open2(\*IN, \*OUT, "make -C $ENV{SRC} O=$buildRoot config SHELL=bash ARCH=$ENV{ARCH} CC=$ENV{CC} HOSTCC=$ENV{HOSTCC} HOSTCXX=$ENV{HOSTCXX}");
+    my $pid = open2(\*IN, \*OUT, "make -C $ENV{SRC} O=$buildRoot config SHELL=bash ARCH=$ENV{ARCH} CC=$ENV{CC} HOSTCC=$ENV{HOSTCC} HOSTCXX=$ENV{HOSTCXX} $makeFlags");
 
     # Parse the output, look for questions and then send an
     # appropriate answer.
diff --git a/pkgs/os-specific/linux/kernel/generic.nix b/pkgs/os-specific/linux/kernel/generic.nix
index b35c84513e69e..f208da7f30ec7 100644
--- a/pkgs/os-specific/linux/kernel/generic.nix
+++ b/pkgs/os-specific/linux/kernel/generic.nix
@@ -116,6 +116,8 @@ let
     # e.g. "bzImage"
     kernelTarget = stdenv.hostPlatform.linux-kernel.target;
 
+    makeFlags = lib.optionals (stdenv.hostPlatform.linux-kernel ? makeFlags) stdenv.hostPlatform.linux-kernel.makeFlags;
+
     prePatch = kernel.prePatch + ''
       # Patch kconfig to print "###" after every question so that
       # generate-config.pl from the generic builder can answer them.
@@ -137,13 +139,15 @@ let
       make -C . O="$buildRoot" $kernelBaseConfig \
           ARCH=$kernelArch \
           HOSTCC=$HOSTCC HOSTCXX=$HOSTCXX HOSTAR=$HOSTAR HOSTLD=$HOSTLD \
-          CC=$CC OBJCOPY=$OBJCOPY OBJDUMP=$OBJDUMP READELF=$READELF
+          CC=$CC OBJCOPY=$OBJCOPY OBJDUMP=$OBJDUMP READELF=$READELF \
+          $makeFlags
 
       # Create the config file.
       echo "generating kernel configuration..."
       ln -s "$kernelConfigPath" "$buildRoot/kernel-config"
       DEBUG=1 ARCH=$kernelArch KERNEL_CONFIG="$buildRoot/kernel-config" AUTO_MODULES=$autoModules \
-           PREFER_BUILTIN=$preferBuiltin BUILD_ROOT="$buildRoot" SRC=. perl -w $generateConfig
+        PREFER_BUILTIN=$preferBuiltin BUILD_ROOT="$buildRoot" SRC=. MAKE_FLAGS="$makeFlags" \
+        perl -w $generateConfig
     '';
 
     installPhase = "mv $buildRoot/.config $out";
-- 
cgit 1.4.1