Build of nspr with android toolchain

# [tuscan]
# Server = file:///var/cache/pacman/pkg/

# :: Synchronizing package databases...
# downloading tuscan.db...

# /toolchain_root/arm-linux-androideabi --> /sysroot/arm-linux-androideabi
# /toolchain_root/COPYING3.LIB --> /sysroot/COPYING3.LIB
# /toolchain_root/sysroot --> /sysroot/sysroot
# /toolchain_root/COPYING.RUNTIME --> /sysroot/COPYING.RUNTIME
# /toolchain_root/lib --> /sysroot/lib
# /toolchain_root/SOURCES --> /sysroot/SOURCES
# /toolchain_root/lib64 --> /sysroot/lib64
# /toolchain_root/share --> /sysroot/share
# /toolchain_root/bin --> /sysroot/bin
# /toolchain_root/COPYING --> /sysroot/COPYING
# /toolchain_root/COPYING3 --> /sysroot/COPYING3
# /toolchain_root/COPYING.LIB --> /sysroot/COPYING.LIB
# /toolchain_root/include --> /sysroot/include
# /toolchain_root/libexec --> /sysroot/libexec

# ==> Making package: nspr 4.12-1 (Tue Apr 4 21:52:47 UTC 2017)
# ==> Checking runtime dependencies...
# ==> Checking buildtime dependencies...
# ==> WARNING: Using existing $srcdir/ tree
# ==> Starting build()...
# checking build system type... x86_64-unknown-linux-gnu
# checking host system type... arm-linux-android
# checking target system type... arm-linux-android
# configure: error: You must specify --with-android-ndk=/path/to/ndk when targeting Android.
# ==> ERROR: A failure occurred in build().
# Aborting...

# This file contains any messages produced by compilers while
# running configure, to aid debugging if configure makes a mistake.
#
# It was created by configure, which was
# generated by GNU Autoconf 2.69. Invocation command line was
#
# $ ./nspr/configure --build=x86_64-unknown-linux --host=arm-linux-androideabi --prefix=/usr --libdir=/usr/lib --includedir=/usr/include/nspr --enable-optimize --disable-debug --enable-64bit
#
# ## --------- ##
# ## Platform. ##
# ## --------- ##
#
# hostname = 807fbe89cae7
# uname -m = x86_64
# uname -r = 4.10.6-1-ARCH
# uname -s = Linux
# uname -v = #1 SMP PREEMPT Mon Mar 27 08:28:22 CEST 2017
#
# /usr/bin/uname -p = unknown
# /bin/uname -X = unknown
#
# /bin/arch = unknown
# /usr/bin/arch -k = unknown
# /usr/convex/getsysinfo = unknown
# /usr/bin/hostinfo = unknown
# /bin/machine = unknown
# /usr/bin/oslevel = unknown
# /bin/universe = unknown
#
# PATH: /sysroot/bin
# PATH: /sysroot/libexec/gcc/arm-linux-androideabi/4.8
# PATH: /usr/local/sbin
# PATH: /usr/local/bin
# PATH: /usr/sbin
# PATH: /usr/bin
# PATH: /sbin
# PATH: /bin
#
#
# ## ----------- ##
# ## Core tests. ##
# ## ----------- ##
#
# configure:2383: checking build system type
# configure:2397: result: x86_64-unknown-linux-gnu
# configure:2417: checking host system type
# configure:2430: result: arm-linux-android
# configure:2450: checking target system type
# configure:2463: result: arm-linux-android
# configure:2675: error: You must specify --with-android-ndk=/path/to/ndk when targeting Android.
#
# ## ---------------- ##
# ## Cache variables. ##
# ## ---------------- ##
#
# ac_cv_build=x86_64-unknown-linux-gnu
# ac_cv_env_CCC_set=
# ac_cv_env_CCC_value=
# ac_cv_env_CC_set=set
# ac_cv_env_CC_value=arm-linux-androideabi-gcc
# ac_cv_env_CFLAGS_set=set
# ac_cv_env_CFLAGS_value=
# ac_cv_env_CPPFLAGS_set=set
# ac_cv_env_CPPFLAGS_value=
# ac_cv_env_CPP_set=
# ac_cv_env_CPP_value=
# ac_cv_env_CXXFLAGS_set=set
# ac_cv_env_CXXFLAGS_value=
# ac_cv_env_CXX_set=set
# ac_cv_env_CXX_value=arm-linux-androideabi-g++
# ac_cv_env_LDFLAGS_set=set
# ac_cv_env_LDFLAGS_value=
# ac_cv_env_LIBS_set=
# ac_cv_env_LIBS_value=
# ac_cv_env_build_alias_set=set
# ac_cv_env_build_alias_value=x86_64-unknown-linux
# ac_cv_env_host_alias_set=set
# ac_cv_env_host_alias_value=arm-linux-androideabi
# ac_cv_env_target_alias_set=
# ac_cv_env_target_alias_value=
# ac_cv_host=arm-linux-android
# ac_cv_target=arm-linux-android
#
# ## ----------------- ##
# ## Output variables. ##
# ## ----------------- ##
#
# AIX_LINK_OPTS=''
# AR=''
# AR_FLAGS=''
# AS=''
# ASFLAGS=''
# ASM_SUFFIX=''
# CC='arm-linux-androideabi-gcc'
# CCACHE=''
# CFLAGS=''
# CPP=''
# CPPFLAGS=''
# CPU_ARCH=''
# CROSS_COMPILE=''
# CXX='arm-linux-androideabi-g++'
# CXXFLAGS=''
# CYGWIN_WRAPPER=''
# DEFINES=''
# DEFS=''
# DLLFLAGS=''
# DLL_SUFFIX=''
# DSO_CFLAGS=''
# DSO_LDOPTS=''
# ECHO_C=''
# ECHO_N='-n'
# ECHO_T=''
# EGREP=''
# ENABLE_STRIP=''
# EXEEXT=''
# EXEFLAGS=''
# FILTER=''
# GCC_USE_GNU_LD=''
# GNU_CC=''
# GREP=''
# HOST_CC=''
# HOST_CFLAGS=''
# HOST_LDFLAGS=''
# IMPLIB=''
# LD=''
# LDFLAGS=''
# LIBNSPR='-L$(dist_libdir) -lnspr$(MOD_MAJOR_VERSION)'
# LIBOBJS=''
# LIBPLC='-L$(dist_libdir) -lplc$(MOD_MAJOR_VERSION)'
# LIBS=''
# LIB_SUFFIX=''
# LTLIBOBJS=''
# MACOSX_DEPLOYMENT_TARGET=''
# MACOS_SDK_DIR=''
# MDCPUCFG_H=''
# MKSHLIB=''
# MOD_MAJOR_VERSION='4'
# MOD_MINOR_VERSION='12'
# MOD_PATCH_VERSION='0'
# MOZILLA_CLIENT=''
# MOZ_DEBUG='1'
# MOZ_DEBUG_SYMBOLS=''
# MOZ_OBJFORMAT=''
# MOZ_OPTIMIZE=''
# MSC_VER=''
# MT=''
# NEXT_ROOT=''
# NOSUCHFILE='/no-such-file'
# NSINSTALL='$(MOD_DEPTH)/config/$(OBJDIR_NAME)/nsinstall'
# NSPR_MODNAME='nspr20'
# OBJDIR='$(OBJDIR_NAME)'
# OBJDIR_NAME='.'
# OBJECT_MODE=''
# OBJEXT=''
# OBJ_SUFFIX=''
# OPTIMIZER=''
# OS_ARCH=''
# OS_DLLFLAGS=''
# OS_LIBS=''
# OS_RELEASE=''
# OS_TARGET=''
# OS_TEST=''
# PACKAGE_BUGREPORT=''
# PACKAGE_NAME=''
# PACKAGE_STRING=''
# PACKAGE_TARNAME=''
# PACKAGE_URL=''
# PACKAGE_VERSION=''
# PATH_SEPARATOR=':'
# PERL=''
# PROFILE_GEN_CFLAGS=''
# PROFILE_GEN_LDFLAGS=''
# PROFILE_USE_CFLAGS=''
# PROFILE_USE_LDFLAGS=''
# PR_MD_ARCH_DIR=''
# PR_MD_ASFILES=''
# PR_MD_CSRCS=''
# RANLIB=''
# RC=''
# RCFLAGS=''
# RELEASE_OBJDIR_NAME=''
# RESOLVE_LINK_SYMBOLS=''
# SHELL='/bin/sh'
# SHELL_OVERRIDE=''
# STRIP=''
# SYMBIAN_SDK_DIR=''
# ULTRASPARC_LIBRARY=''
# USE_64=''
# USE_BTHREADS=''
# USE_CPLUS=''
# USE_IPV6=''
# USE_N32=''
# USE_NSPR_THREADS=''
# USE_PTHREADS=''
# USE_USER_PTHREADS=''
# USE_X32=''
# VISIBILITY_FLAGS=''
# WHOAMI=''
# WINDRES=''
# WRAP_LDFLAGS=''
# WRAP_SYSTEM_INCLUDES=''
# ac_ct_CC=''
# ac_ct_CXX=''
# bindir='${exec_prefix}/bin'
# build='x86_64-unknown-linux-gnu'
# build_alias='x86_64-unknown-linux'
# build_cpu='x86_64'
# build_os='linux-gnu'
# build_vendor='unknown'
# datadir='${datarootdir}'
# datarootdir='${prefix}/share'
# dist_bindir=''
# dist_includedir=''
# dist_libdir=''
# dist_prefix=''
# docdir='${datarootdir}/doc/${PACKAGE}'
# dvidir='${docdir}'
# exec_prefix='NONE'
# host='arm-linux-android'
# host_alias='arm-linux-androideabi'
# host_cpu='arm'
# host_os='android'
# host_vendor='linux'
# htmldir='${docdir}'
# includedir='/usr/include/nspr'
# infodir='${datarootdir}/info'
# libdir='/usr/lib'
# libexecdir='${exec_prefix}/libexec'
# localedir='${datarootdir}/locale'
# localstatedir='${prefix}/var'
# mandir='${datarootdir}/man'
# oldincludedir='/usr/include'
# pdfdir='${docdir}'
# prefix='/usr'
# program_transform_name='s,x,x,'
# psdir='${docdir}'
# sbindir='${exec_prefix}/sbin'
# sharedstatedir='${prefix}/com'
# sysconfdir='${prefix}/etc'
# target='arm-linux-android'
# target_alias=''
# target_cpu='arm'
# target_os='android'
# target_vendor='linux'
#
# ## ----------- ##
# ## confdefs.h. ##
# ## ----------- ##
#
# /* confdefs.h */
# #define PACKAGE_NAME ""
# #define PACKAGE_TARNAME ""
# #define PACKAGE_VERSION ""
# #define PACKAGE_STRING ""
# #define PACKAGE_BUGREPORT ""
# #define PACKAGE_URL ""
#
# configure: exit 1