Thanks for filing the issue!

As the issue seems to be related to building a system software "Ninja", which is out of scope for ET team to do. Hence adding label TE-NeedsTriageHelp.

sorry if   you had a misunderstood


but when i say "Ninja bootstraping" i'm talking about this command 


 python2 tools/gn/bootstrap/bootstrap.py --gn-gen-args "${_flags[*]}"

this commit caused it 



if we revert it may work at desktop (testing with 65.0.3234.0)

https://chromium.googlesource.com/chromium/src/+/2b31dbb2b212be2402e583d0ce53d30fb7892a5c%5E%21/#F3

it may work (i'm testing it,  injecting use_lld=false as a flag)            


ninja: error: '/home/senpai/bm/asp/chromium/trunk/nt/src/chromium-65.0.3324.0/base/lazy_instance.cc', needed by 'base/lazy_instance.o', missing and no known rule to make it

all base folder may be broken

Adding Build component and Build=Tools-GN as this appears to be related to gn bootstrapping.

The original error from the OPs paste is:

Building gn manually in a temporary directory for bootstrapping...
Traceback (most recent call last):
  File "tools/gn/bootstrap/bootstrap.py", line 866, in <module>
    sys.exit(main(sys.argv[1:]))
  File "tools/gn/bootstrap/bootstrap.py", line 133, in main
    return run_build(tempdir, options)
  File "tools/gn/bootstrap/bootstrap.py", line 75, in run_build
    build_gn_with_ninja_manually(tempdir, options)
  File "tools/gn/bootstrap/bootstrap.py", line 228, in build_gn_with_ninja_manually
    if is_android:
NameError: global name 'is_android' is not defined

juanka89: It would be of immense help if you could provide the environment in which you are building, and the exact steps you are taking to reproduce this (e.g. which tarball you downloaded, where and how you extracted it, and what commands you then run to try and build Chromium).

 Issue 803498  has been merged into this issue.

 Issue 803518  has been merged into this issue.

env,   normal archlinux

build-setup, buildscript

python: 2.7.14

arch. 64

distro: manjaro

tarball https://gsdview.appspot.com/chromium-browser-official/chromium-65.0.3324.0.tar.xz

extracted via tar Jvxf chromium-65.0.3324.0.tar.xz (with pkgbuild)



system libs used
https://p.teknik.io/VVXKR

gn flags
https://p.teknik.io/Raw/2frMZ

clang: from google


exports
https://p.teknik.io/Raw/6Eamg


command with the error
 python2 tools/gn/bootstrap/bootstrap.py --gn-gen-args "${_flags[*]}"

if i revert this commit locally (for skip the first trouble)

https://chromium.googlesource.com/chromium/src/+/2b31dbb2b212be2402e583d0ce53d30fb7892a5c%5E%21/#F3


i got many missing files at base/ folder  



just like
chromium-65.0.3324.0/base/lazy_instance.cc', needed by 'base/lazy_instance.o', missing and no known rule to make it

OP you can apply this patch in the meantime to fix it:
https://chromium-review.googlesource.com/c/chromium/src/+/874870

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4c76252228505ce85f2965f71facaf41407f13c4

commit 4c76252228505ce85f2965f71facaf41407f13c4
Author: Tom Anderson <thomasanderson@chromium.org>
Date: Thu Jan 18 19:53:43 2018

Fix gn bootstrap

BUG= 803324 
R=dpranke

Change-Id: Ib8a66495b9657da130a6608e6dacf6cf471cd504
Reviewed-on: https://chromium-review.googlesource.com/874870
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Commit-Queue: Thomas Anderson <thomasanderson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#530236}
[modify] https://crrev.com/4c76252228505ce85f2965f71facaf41407f13c4/tools/gn/bootstrap/bootstrap.py

sucess

thanks