From d9020c648ee01b378390cdfacf5267dd1c18566b Mon Sep 17 00:00:00 2001
From: Hannes Winkler <hanneswinkler2000@web.de>
Date: Wed, 11 Aug 2021 13:09:36 +0200
Subject: [PATCH 1/2] don't build flutter SDK artifacts for armv7

---
 BUILD.gn | 3 ++-
 DEPS     | 9 +++++++++
 tools/gn | 2 +-
 3 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/BUILD.gn b/BUILD.gn
index 147cb941532f8..133e091360e32 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -47,7 +47,8 @@ if (flutter_prebuilt_dart_sdk) {
 # Flutter SDK artifacts should only be built when either doing host builds, or
 # for cross-compiled desktop targets.
 _build_engine_artifacts =
-    current_toolchain == host_toolchain || (is_linux && !is_chromeos) || is_mac
+    current_toolchain == host_toolchain ||
+    (is_linux && !is_chromeos && current_cpu != "arm") || is_mac
 
 group("dart_sdk") {
   if (_build_engine_artifacts) {
diff --git a/DEPS b/DEPS
index a87bf7000588f..89fe8ff08a2e8 100644
--- a/DEPS
+++ b/DEPS
@@ -739,6 +739,15 @@ hooks = [
       'src/build/linux/sysroot_scripts/install-sysroot.py',
       '--arch=arm64'],
   },
+  {
+    'name': 'linux_sysroot_arm',
+    'pattern': '.',
+    'condition': 'download_linux_deps',
+    'action': [
+      'python3',
+      'src/build/linux/sysroot_scripts/install-sysroot.py',
+      '--arch=arm'],
+  },
   {
     'name': 'pub get --offline',
     'pattern': '.',
diff --git a/tools/gn b/tools/gn
index 1d82182c73c34..7fdff1ff1b47f 100755
--- a/tools/gn
+++ b/tools/gn
@@ -88,7 +88,7 @@ def is_host_build(args):
     # target_os='linux' and linux-cpu='arm64'
     # TODO(fujino): make host platform explicit
     #   https://github.com/flutter/flutter/issues/79403
-    return args.target_os is None or args.target_os == 'linux'
+    return args.target_os is None or (args.target_os == 'linux' and args.linux_cpu == 'arm64')
 
 # Determines whether a prebuilt Dart SDK can be used instead of building one.
 # We can use a prebuilt Dart SDK when:

From 1f69319212fa7e538bd5c2e2f73ed8a2883e2412 Mon Sep 17 00:00:00 2001
From: Hannes Winkler <hanneswinkler2000@web.de>
Date: Fri, 5 Nov 2021 15:14:22 +0100
Subject: [PATCH 2/2] add todo link in BUILD.gn - don't download arm sysroot on
 checkout

---
 BUILD.gn | 2 ++
 DEPS     | 9 ---------
 2 files changed, 2 insertions(+), 9 deletions(-)

diff --git a/BUILD.gn b/BUILD.gn
index 133e091360e32..cca086c104479 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -46,6 +46,8 @@ if (flutter_prebuilt_dart_sdk) {
 
 # Flutter SDK artifacts should only be built when either doing host builds, or
 # for cross-compiled desktop targets.
+# TODO: We can't build the engine artifacts for arm (32-bit) right now;
+# see https://github.com/flutter/flutter/issues/74322
 _build_engine_artifacts =
     current_toolchain == host_toolchain ||
     (is_linux && !is_chromeos && current_cpu != "arm") || is_mac
diff --git a/DEPS b/DEPS
index 89fe8ff08a2e8..a87bf7000588f 100644
--- a/DEPS
+++ b/DEPS
@@ -739,15 +739,6 @@ hooks = [
       'src/build/linux/sysroot_scripts/install-sysroot.py',
       '--arch=arm64'],
   },
-  {
-    'name': 'linux_sysroot_arm',
-    'pattern': '.',
-    'condition': 'download_linux_deps',
-    'action': [
-      'python3',
-      'src/build/linux/sysroot_scripts/install-sysroot.py',
-      '--arch=arm'],
-  },
   {
     'name': 'pub get --offline',
     'pattern': '.',