raises syntax error on Python 3



Firefox Build System
Bootstrap Configuration
3 years ago
3 days ago


(Reporter: altblitz, Unassigned)


Firefox Tracking Flags

(Not tracked)




3 years ago
User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:44.0) Gecko/20100101 Firefox/44.0
Build ID: 20150921073455

Steps to reproduce:

'If you don’t have one yet, create a "src" directory for yourself under your home directory: cd ~ && mkdir src' - done.
'Next download the script and save it in your src/ directory.' - done
'And finally, in your terminal: cd ~/src and start the bootstrapper like this:
python' - failed

[foo@ba ~/src ] uname  -a
Linux inode 4.2.1-1-ARCH #1 SMP PREEMPT Tue Sep 22 06:57:07 CEST 2015 x86_64 GNU/Linux
[foo@ba ~/src ] python --version
Python 3.4.3

Actual results:

[foo@bar ~/src ] python  
Could not load the bootstrap Python environment.
This should never happen. Consider filing a bug.
Missing parentheses in call to 'print' (, line 67)

Expected results:

'... follow the prompts.'

Comment 1

3 years ago
In Arch python should be python2

Your version of Mercurial (3.5.1) is sufficiently modern.
Your version of Python (2.7.10) is new enough.

Your system should be ready to build Firefox for Desktop! If you have not already,
obtain a copy of the source code by running:
    hg clone
Or, if you prefer Git:
    git clone

python2  6.71s user 1.21s system 12% cpu 1:03.48 total

Comment 2

3 years ago
Yeah, this is a Python 3 compatibility problem. We need to make the bootstrapper Python 3 compatible as a lot of distros are shipping Python 3 by default now.

We should at least detect Python 3 and raise an actionable error until we have full Python 3 support.
Component: Mercurial: → Build Config
Product: Developer Services → Core
QA Contact: hwine
Summary: Firefox Onramp: Could not load the bootstrap Python environment → raises syntax error on Python 3
Version: Development/Staging → unspecified


3 months ago
Product: Core → Firefox Build System


3 days ago
Component: General → Bootstrap Configuration
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