From 138d587e3ae169cb288aad59ca9f7db6ca76e190 Mon Sep 17 00:00:00 2001
From: James Robinson <jamesr@google.com>
Date: Thu, 18 Jan 2018 06:05:56 +0000
Subject: [PATCH] [gn] Remove uses of is_fuchsia_host GN variable

Some parts of the Dart build need to be customized when running the
host steps for a build ultimately targeting a Fuchsia build. This was
set by passing a special GN variable indicating that a configuration
was a host configuration targeting a Fuchsia build, but the built-in GN
variable 'target_os' has the same result as it is the same across all
toolchains in a particular build.  This replaces the test:
  is_fuchsia || is_fuchsia_host

with the equivalent:
  target_os == "fuchsia"

and the less common:
  is_fuchsia_host

with:
  target_os != current_os && target_os == "fuchsia"

Change-Id: Iabec1fb2879b234ca44c9e03b2f4a62ffbc6fa4a
Reviewed-on: https://dart-review.googlesource.com/35542
Reviewed-by: Zach Anderson <zra@google.com>
Commit-Queue: Zach Anderson <zra@google.com>
---
 BUILD.gn                    | 10 ++++++----
 build/config/BUILDCONFIG.gn |  8 +-------
 runtime/bin/BUILD.gn        |  4 ++--
 sdk/BUILD.gn                |  2 +-
 4 files changed, 10 insertions(+), 14 deletions(-)

diff --git a/BUILD.gn b/BUILD.gn
index e621934e475..3f93c69511f 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -4,9 +4,11 @@
 
 import("build/dart_host_sdk_toolchain.gni")
 
+targetting_fuchsia = target_os == "fuchsia"
+
 # This target will be built if no target is specified when invoking ninja.
 group("default") {
-  if (is_fuchsia || is_fuchsia_host) {
+  if (targetting_fuchsia) {
     # Fuchsia has run_vm_tests marked testonly.
     testonly = true
   }
@@ -16,7 +18,7 @@ group("default") {
 }
 
 group("most") {
-  if (is_fuchsia || is_fuchsia_host) {
+  if (targetting_fuchsia) {
     # Fuchsia has run_vm_tests marked testonly.
     testonly = true
   }
@@ -32,7 +34,7 @@ group("most") {
 }
 
 group("runtime") {
-  if (is_fuchsia || is_fuchsia_host) {
+  if (targetting_fuchsia) {
     # Fuchsia has run_vm_tests marked testonly.
     testonly = true
   }
@@ -47,7 +49,7 @@ group("runtime") {
 }
 
 group("runtime_kernel") {
-  if (is_fuchsia || is_fuchsia_host) {
+  if (targetting_fuchsia) {
     # Fuchsia has run_vm_tests marked testonly.
     testonly = true
   }
diff --git a/build/config/BUILDCONFIG.gn b/build/config/BUILDCONFIG.gn
index 4dfbaf694ef..ff7b42f7665 100644
--- a/build/config/BUILDCONFIG.gn
+++ b/build/config/BUILDCONFIG.gn
@@ -154,7 +154,6 @@ if (current_os == "win") {
   is_android = false
   is_chromeos = false
   is_fuchsia = false
-  is_fuchsia_host = false
   is_ios = false
   is_linux = false
   is_mac = false
@@ -165,7 +164,6 @@ if (current_os == "win") {
   is_android = false
   is_chromeos = false
   is_fuchsia = false
-  is_fuchsia_host = false
   is_ios = false
   is_linux = false
   is_mac = true
@@ -176,7 +174,6 @@ if (current_os == "win") {
   is_android = true
   is_chromeos = false
   is_fuchsia = false
-  is_fuchsia_host = false
   is_ios = false
   is_linux = false
   is_mac = false
@@ -187,7 +184,6 @@ if (current_os == "win") {
   is_android = false
   is_chromeos = false
   is_fuchsia = false
-  is_fuchsia_host = false
   is_ios = false
   is_linux = true
   is_mac = false
@@ -252,9 +248,7 @@ if (is_linux) {
 }
 
 if (is_clang) {
-  _native_compiler_configs += [
-    "//build/config/clang:extra_warnings",
-  ]
+  _native_compiler_configs += [ "//build/config/clang:extra_warnings" ]
 }
 
 # Optimizations and debug checking.
diff --git a/runtime/bin/BUILD.gn b/runtime/bin/BUILD.gn
index 6afa317adbb..83e59cb4422 100644
--- a/runtime/bin/BUILD.gn
+++ b/runtime/bin/BUILD.gn
@@ -712,7 +712,7 @@ template("dart_executable") {
     if (is_fuchsia) {
       configs -= [ "//build/config:symbol_visibility_hidden" ]
     }
-    if (is_fuchsia_host) {
+    if (target_os != current_os && target_os == "fuchsia") {
       # We already have these in the standalone build, but Fuchsia doesn't
       # have them. They are needed for running Fuchsia binaries built for the
       # host.
@@ -1005,7 +1005,7 @@ action("generate_snapshot_test_dat_file") {
 }
 
 executable("run_vm_tests") {
-  if (is_fuchsia || is_fuchsia_host) {
+  if (target_os == "fuchsia") {
     testonly = true
   }
 
diff --git a/sdk/BUILD.gn b/sdk/BUILD.gn
index 41adf0158ee..5f352ab64e7 100644
--- a/sdk/BUILD.gn
+++ b/sdk/BUILD.gn
@@ -314,7 +314,7 @@ copy_trees("copy_trees") {
 }
 
 # Copies the Dart VM binary into bin/
-if (is_fuchsia_host) {
+if (target_os != current_os && target_os == "fuchsia") {
   # In the Fuchsia build, this has to use a symlink for two reasons.
   # First, it makes the lookup of shared libraries relative to $ORIGIN
   # (Linux) or @loader_path (macOS) find the libraries where they are,