How to exclude a library from the link line of a shared object?

[asharif]

I am building Chromium's _pyautolib.so file, whose generated *.mk file pulls in a particular library (liballocator.a). I understand that this particular library is pulled in because a variable is set (linux_use_tcmalloc). What I want to do is, just for this particular shared object, I want to not include liballocator.a.

By looking at the gyp file which generates _pyautolib.so (http://src.chromium.org/svn/trunk/src/chrome/chrome_tests.gypi search on this page for pyautolib), you can see that it doesn't directly pull in this library. Rather, a few of the dependencies that it lists pull in that library.

I've tried the following approaches without success:

'all_dependent_settings': {

  'dependencies!' : [

  '../base/allocator/allocator.gyp:allocator'

]

}

and this one:

'all_dependent_settings': {

  'linux_use_tcmalloc' : '0'

}

These aren't seem to be working (i.e. liballocator.a still shows up at the link line of _pyautolib.so). Do you have any suggestions on how this can be done without refactoring all the libraries and separating them out into parts which depend on liballocator and parts which don't?

Thanks,

[Ryan Sleevi]

You cannot revoke a GYP dependency that has been injected from a lower layer, particularly when it's multiple layers removed. IIRC, for Pyauto's case, base/allocator/allocator.gyp flows from base/base.gyp.

Since these dependencies can have an effect on how dictionary merging is performed - they may set custom defines, add new dependencies, etc - there's no reasonable way to "unmerge" the dictionaries.

If your pyauto target does not build when 'linux_use_tcmalloc': '1' is true, then it sounds like you should instead be excluding that target from Chromium builds where that is the case, and setup new Chromium bots to build _pyautolib.so and explicitly specify 'linux_use_tcmalloc': '0'.

For Chromium, it's especially problematic to mix and match allocators, so this may be your best bet.