I'm using a separate environment inside docker container to build 32-bit version of libsdl2.

Here's my Dockerfile:

FROM ubuntu:trusty
RUN dpkg --add-architecture i386
RUN apt-get update
RUN apt-get install -y --no-install-recommends gcc-multilib make curl libasound2-dev:i386 libx11-dev:i386 libxext-dev:i386 libgl1-mesa-dev libxrandr-dev:i386 libpulse-dev:i386
RUN curl -s http://libsdl.org/release/SDL2-2.0.7.tar.gz | tar xzf -
WORKDIR /SDL2-2.0.7
ENV CC="gcc -msse2 -march=i686 -m32 -ggdb -O2"
RUN ./configure \
	--disable-dependency-tracking \
	--enable-audio \
	--enable-video \
	--enable-events \
	--disable-render \
	--enable-joystick \
	--disable-haptic \
	--disable-power \
	--enable-threads \
	--enable-timers \
	--enable-loadso \
	--enable-video-opengl \
	--enable-x11-shared \
	--enable-video-x11 \
	--enable-video-x11-xrandr \
	--enable-video-x11-scrnsaver \
	--enable-video-x11-xinput \
	--disable-video-x11-xshape \
	--disable-video-x11-xdbe \
	--disable-libudev \
	--disable-dbus \
	--disable-ibus \
	--enable-sdl-dlopen \
	--disable-video-opengles \
	--disable-cpuinfo \
	--disable-assembly \
	--disable-atomic \
	--enable-alsa-shared \
	--enable-pulseaudio-shared

However during the configure phase it says

checking for PulseAudio 0.9 support... no

And it ends up not including pulseaudio in the build:

Audio drivers   : disk dummy oss alsa(dynamic)

libpulse-simple is present and ldconfig can find it:

ldconfig -p | grep pulse
        libpulse.so.0 (libc6) => /usr/lib/i386-linux-gnu/libpulse.so.0
        libpulse.so (libc6) => /usr/lib/i386-linux-gnu/libpulse.so
        libpulse-simple.so.0 (libc6) => /usr/lib/i386-linux-gnu/libpulse-simple.so.0
        libpulse-simple.so (libc6) => /usr/lib/i386-linux-gnu/libpulse-simple.so
        libpulse-mainloop-glib.so.0 (libc6) => /usr/lib/i386-linux-gnu/libpulse-mainloop-glib.so.0
        libpulse-mainloop-glib.so (libc6) => /usr/lib/i386-linux-gnu/libpulse-mainloop-glib.so