main/postmarketos-mkinitfs: add workaround for x86_64 qemu on aarch64 (MR 5653)

This adds a workaround for:
https://gitlab.com/qemu-project/qemu/-/issues/2560

The tl;dr is that there's a qemu bug that prevents running mkinitfs (or
any go apps) on a aarch64 host using qemu-x86_64. I've basically been
unable to build x86_64 images on my aarch64 system for months now, which
is less than ideal :(

Patch is in mkinitfs 2.6.1, but picked to the older version in master until !5636 is merged

[ci:skip-build]: already built successfully in CI

main/postmarketos-mkinitfs/0001-add-compile-time-flag-to-disable-Go-GC-MR-56.patch

+From d63e60061419cb1cb1591c9f7f5f238d1201b7f1 Mon Sep 17 00:00:00 2001
+From: Clayton Craft <clayton@craftyguy.net>
+Date: Sat, 28 Sep 2024 08:11:19 -0700
+Subject: [PATCH] add compile-time flag to disable Go GC (MR 56)
+
+I hate this, but it's the only good way I could find to allow working around this ugly QEMU bug:
+https://gitlab.com/qemu-project/qemu/-/issues/2560
+---
+ Makefile             | 5 +++++
+ cmd/mkinitfs/main.go | 8 ++++++++
+ 2 files changed, 13 insertions(+)
+
+diff --git a/Makefile b/Makefile
+index e4fbcdd..0b1e841 100644
+--- a/Makefile
++++ b/Makefile
+@@ -13,6 +13,11 @@ GOFLAGS?=
+ LDFLAGS+=-s -w -X main.Version=$(VERSION)
+ RM?=rm -f
+ GOTEST=go test -count=1 -race
++DISABLE_GOGC?=
++
++ifeq ($(DISABLE_GOGC),1)
++	LDFLAGS+=-X main.DisableGC=true
++endif
+ 
+ GOSRC!=find * -name '*.go'
+ GOSRC+=go.mod go.sum
+diff --git a/cmd/mkinitfs/main.go b/cmd/mkinitfs/main.go
+index 138667b..6494504 100644
+--- a/cmd/mkinitfs/main.go
++++ b/cmd/mkinitfs/main.go
+@@ -9,6 +9,8 @@ import (
+ 	"log"
+ 	"os"
+ 	"path/filepath"
++	"runtime/debug"
++	"strings"
+ 	"time"
+ 
+ 	"gitlab.com/postmarketOS/postmarketos-mkinitfs/internal/archive"
+@@ -26,8 +28,14 @@ import (
+ 
+ // set at build time
+ var Version string
++var DisableGC string
+ 
+ func main() {
++	// To allow working around silly GC-related issues, like https://gitlab.com/qemu-project/qemu/-/issues/2560
++	if strings.ToLower(DisableGC) == "true" {
++		debug.SetGCPercent(-1)
++	}
++
+ 	retCode := 0
+ 	defer func() { os.Exit(retCode) }()
+ 
+-- 
+2.46.2
+

main/postmarketos-mkinitfs/APKBUILD

@@ -2,7 +2,7 @@
 # Co-Maintainer: Clayton Craft <clayton@craftyguy.net>
 pkgname=postmarketos-mkinitfs
 pkgver=2.5.1
-pkgrel=0
+pkgrel=1
 pkgdesc="Tool to generate initramfs images for postmarketOS"
 url="https://postmarketos.org"
 depends="
@@ -26,6 +26,7 @@ triggers="$pkgname.trigger=\
 source="
 	https://gitlab.com/postmarketOS/postmarketos-mkinitfs/-/archive/$pkgver/postmarketos-mkinitfs-$pkgver.tar.gz
 	https://gitlab.com/api/v4/projects/postmarketOS%2Fpostmarketos-mkinitfs/packages/generic/mkinitfs-vendor-$pkgver/$pkgver/mkinitfs-vendor-$pkgver.tar.gz
+	0001-add-compile-time-flag-to-disable-Go-GC-MR-56.patch
 	"
 
 install="$pkgname.post-upgrade"
@@ -47,7 +48,15 @@ prepare() {
 
 build() {
 	unset LDFLAGS  # passed to Go as linker flags, which are invalid
-	make VERSION="$pkgver"
+
+	# Go garbage collector malfunctions when running x86_64 binaries in QEMU on
+	# an aarch64 host. See: https://gitlab.com/qemu-project/qemu/-/issues/2560
+	case "$CARCH" in
+	x86_64)
+		make VERSION="$pkgver" DISABLE_GOGC=1 ;;
+	*)
+		make VERSION="$pkgver" ;;
+	esac
 }
 
 package() {
@@ -61,4 +70,5 @@ check() {
 sha512sums="
 6f2e5c8281a8e6b340f2288b31fb102dcc98480e8bf905bf57a54a81d36a5615b194f0a56f5cd3be207784278257eb6ee3dfecaccb60c3332f4d0f45bafedaa3  postmarketos-mkinitfs-2.5.1.tar.gz
 420e4bd8126f765c18b3ea48b2dc7356727958826dbe1086b753f5d46bc9b56d25ed668db8f9f4e8c9d5b1e943105850071c9c3ce442daf12eaa80516e973372  mkinitfs-vendor-2.5.1.tar.gz
+2af899c69cbdc84ca85f2a5fe609974b2b9e4c0389d9487596d86d403e55b09fdc2e7daf4452bf33b8a27a2b37339d9311b8d1f903074a1410689665425b7d68  0001-add-compile-time-flag-to-disable-Go-GC-MR-56.patch
 "