I was trying to make some modifications to android emulator and was unable to find good set of instructions for the compiling the same.

Here are mine.

# Get the source code.
git clone https://android.googlesource.com/platform/external/qemu
cd qemu
# Install required dependencies.
sudo apt-get install gcc-multilib libesd0-dev libx11-dev \
 libxext-dev libasound2-dev libpulse-dev \
# Install ia32 libraries (missing from default ubuntu 13.10).
sudo apt-get install libgtk2.0-0:i386 libpangox-1.0-0:i386 \
 libpangoxft-1.0-0:i386 libidn11:i386 libglu1-mesa:i386 
# Configure and build the emulator binary.
./android-configure.sh --no-gles --no-tests --cc=/usr/bin/gcc
make -j16
# The emulator binaries are in objs directory.