Solving multilib version problems

It seems your libgcc.x86_64 has a different version than the libgcc.i686 you are trying to install (4.4.7-3 vs. 4.4.7-4). Try to update the x86_64 lib together with the installation of the i686-lib:

yum install libgcc.x86_64 libgcc.i686

I've hit this after interrupting yum update (during an ansible run in my case). After reading this thread I eventually fixed it with:

package-cleanup --cleandupes

Though before that I'd also tried running commands as @etagenklo suggested, and also tried:

yum-complete-transaction
yum-complete-transaction --cleanup-only
yum check                # report generally
package-cleanup --dupes  # report on duplicate packages in particular