Hi,
I'm seeing the following build error trying to build from the current master branch (1ac806b) of http://git.linaro.org/toolchain/binutils-gdb.
make[3]: *** No rule to make target `-L../zlib', needed by `run'. Stop. make[3]: *** Waiting for unfinished jobs.... make[3]: Leaving directory `gdb/sim/arm'
The following commit predating the zlib changes appears to build without error.
b19a8f8545100a08ee2a64c05631aff6f651faa1
Thanks, Chris