Import symbols into google namespace to maintain backwards compatibility about gflags HOT 10 OPEN

This has been implemented. In fact, any number of alternative namespaces can be 
configured next to the default/primary namespace using the GFLAGS_NAMESPACE 
CMake variable.

See commit 659b440f of the feature/#83-alternative-namespace branch.

Link to commit: 
https://code.google.com/p/gflags/source/detail?r=659b440f9e403c9080eb304efc53b93
8c63cbe47&name=feature/#83-alternative-namespace

This branch works well for me; I can link glog to it and I don't have to change 
existing code. Please include it in a future release!

Hi Carles, thanks for the feedback. I will make another patch release available 
soon which hopefully concludes the transition to the new build system 
configuration and namespace.

Great! Thanks for your work.

I'm running into issues compiling glog because of this (running fresh built 
2.1.1) - any chance someone could post how I'd set the CMake variable 
GFLAGS_NAMESPACE so I can workaround the issue? Or is 2.1.2 release imminent?

Thanks for bumping it up... soon was meant to be sooner ;)

Regarding the CMake settings of 2.1.1, you will need to change GFLAGS_NAMESPACE 
to "google" and make sure that GFLAGS_INCLUDE_DIR is "gflags". See issue #80.

I've just had a chance to return to this. Not knowing anything about cmake, 
I've edited CMakeLists.txt & changed the line

set (GFLAGS_NAMESPACE   "${PACKAGE_NAME}" CACHE STRING "C++ namespace 
identifier of gflags library.")

to

set (GFLAGS_NAMESPACE   "google" CACHE STRING "C++ namespace identifier of 
gflags library.")

Then built and installed as per normal instructions. However when I try to 
compile glog I get a fail, with the error message

/usr/local/lib/libgflags.a: could not read symbols: Bad value

I guess I'm doing something wrong still...

For projects that use a system-installed gflags development package this is 
still more or less a problem. Since you don't have control of the CMake 
GFLAGS_NAMESPACE variable, and the config.h will not be distributed, there's no 
way to determine gflags version and namespace.

This could export a define for the namespace, and make sure that ends up in 
gflags.h. How about:

#define GFLAGS_NAMESPACE gflags

Thanks for the suggestion. As a matter of fact, such define was already added 
by commit a93de007 
(https://code.google.com/p/gflags/source/detail?r=a93de007a65eea5f0eea1eb830788d
bdb7c17112&name=feature/#83-alternative-namespace) in a feature branch.