Drake: Setting GCC default to 4.9

[peteflorence]

Going through new Ubuntu build instructions, http://drake002.csail.mit.edu/drake/sphinx/ubuntu.html

Think we need a line that ensures switching default over to GCC 4.9, I'm getting message below,. gcc -v says I am still on 4.8.5

I'll look up a fix. Also is the Sphinx documentation in git somewhere, and can I contribute to that directly?

peteflo@peteflo:~/drake-distro$ env CXX=g++-4.9 CC=gcc-4.9 make options
Configuring with CMAKE_FLAGS: -DCMAKE_BUILD_TYPE=Release
CMake Error at CMakeLists.txt:5 (message):
GCC version must be at least 4.9

-- Configuring incomplete, errors occurred!
See also "/home/peteflo/drake-distro/pod-build/CMakeFiles/CMakeOutput.log".
make: *** [configure] Error 1

[liangfok]

Yes, the Sphinx documentation is in drake/doc.

[peteflorence]

Thanks @liangfok

[jwnimmer-tri]

I believe the instructions are correct? Did you install g++-4.9-multilib? What does g++-4.9 --version report on the command line (without CMake or make involved)?

[peteflorence]

Problem solved, thanks @patmarion . I had run make once prior to to going through platform-specific instructions. rm -rf pod-build fixed my problem, it must have been cached on 4.8.5

[jwnimmer-tri]

Aha! Another vote for #1973's pending tip of:

• _The build system isn't working? git clean -fdx from orbit, it's the only way to be sure_.