859078 - mach build fails trying to write warnings.json

Status: RESOLVED DUPLICATE of bug 857332

(Firefox Build System :: Mach Core, enhancement)

Description

[Amir Aharoni]

I tried to build mozilla-central on Fedora 18. I got this error:

-------------------
130:31.72 1436 compiler warnings present.
Error running mach:

    ['build']

The error occurred in code that was called by the mach command. This is either
a bug in the called code itself or in the way that mach is calling it.

You should consider filing a bug for this issue.

If filing a bug, please include the full output of mach, including this error
message.

The details of the failure are as follows:

IOError: [Errno 2] No such file or directory: u'/home/amire80/dev/mozilla-central/obj-x86_64-unknown-linux-gnu/.mozbuild/warnings.json'

  File "/home/amire80/dev/mozilla-central/python/mozbuild/mozbuild/mach_commands.py", line 115, in build
    warnings_database.save_to_file(warnings_path)
  File "/home/amire80/dev/mozilla-central/python/mozbuild/mozbuild/compilation/warnings.py", line 268, in save_to_file
    with open(filename, 'wb') as fh:
-------------------

On IRC Ms2ger suggested running hg log -r 4a6fd35a9a53. Here's its output:

-------------------
[amire80@theodor mozilla-central]$ hg log -r 4a6fd35a9a53
changeset:   127496:4a6fd35a9a53
user:        Matt Brubeck <[e-mail]>
date:        Wed Apr 03 10:15:12 2013 -0700
summary:     Bug 857332 - Normalize topobjdir to an absolute path in mozbuild.base [r=gps]
-------------------