Build of xsp with vanilla toolchain

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

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

# ==> Making package: xsp 3.0.11-1 (Wed Aug 24 14:20:22 UTC 2016)
# ==> Checking runtime dependencies...
# ==> Checking buildtime dependencies...
# ==> WARNING: Using existing $srcdir/ tree
# ==> Starting build()...
# Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/\${ <-- HERE ([^ \t=:+{}]+)}/ at /usr/sbin/automake line 3936.
# Running aclocal -I build/m4/shamrock -I build/m4/shave ...
# Running autoconf ...
# Running automake --gnu --add-missing --force --copy ...
# WARNING: I am going to run configure without any arguments.
# Running ./configure --enable-maintainer-mode ...
# checking build system type... x86_64-unknown-linux-gnu
# checking host system type... x86_64-unknown-linux-gnu
# checking target system type... x86_64-unknown-linux-gnu
# checking for a BSD-compatible install... /usr/bin/install -c
# checking whether build environment is sane... yes
# checking for a thread-safe mkdir -p... /usr/sbin/mkdir -p
# checking for gawk... gawk
# checking whether make sets $(MAKE)... yes
# checking whether make supports nested variables... yes
# checking whether to enable maintainer-specific portions of Makefiles... yes
# checking for gawk... (cached) gawk
# checking for pkg-config... /usr/sbin/pkg-config
# checking pkg-config is at least version 0.9.0... yes
# checking for MONO_MODULE... yes
# checking for gmcs... no
# configure: error: You need to install 'gmcs'
# Error: Could not run ./configure, which is required to configure xsp
# ==> 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 xsp configure 3.0, which was
# generated by GNU Autoconf 2.69. Invocation command line was
#
# $ ./configure --enable-maintainer-mode
#
# ## --------- ##
# ## Platform. ##
# ## --------- ##
#
# hostname = ad39ee65dcd7
# uname -m = x86_64
# uname -r = 4.7.1-1-ARCH
# uname -s = Linux
# uname -v = #1 SMP PREEMPT Wed Aug 17 08:13:35 CEST 2016
#
# /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: /usr/local/sbin
# PATH: /usr/local/bin
# PATH: /usr/sbin
# PATH: /usr/bin
# PATH: /sbin
# PATH: /bin
#
#
# ## ----------- ##
# ## Core tests. ##
# ## ----------- ##
#
# configure:1845: checking build system type
# configure:1859: result: x86_64-unknown-linux-gnu
# configure:1879: checking host system type
# configure:1892: result: x86_64-unknown-linux-gnu
# configure:1912: checking target system type
# configure:1925: result: x86_64-unknown-linux-gnu
# configure:1969: checking for a BSD-compatible install
# configure:2037: result: /usr/bin/install -c
# configure:2048: checking whether build environment is sane
# configure:2103: result: yes
# configure:2254: checking for a thread-safe mkdir -p
# configure:2293: result: /usr/sbin/mkdir -p
# configure:2300: checking for gawk
# configure:2316: found /usr/sbin/gawk
# configure:2327: result: gawk
# configure:2338: checking whether make sets $(MAKE)
# configure:2360: result: yes
# configure:2389: checking whether make supports nested variables
# configure:2406: result: yes
# configure:2533: checking whether to enable maintainer-specific portions of Makefiles
# configure:2542: result: yes
# configure:2610: checking for gawk
# configure:2637: result: gawk
# configure:2734: checking for pkg-config
# configure:2752: found /usr/sbin/pkg-config
# configure:2764: result: /usr/sbin/pkg-config
# configure:2789: checking pkg-config is at least version 0.9.0
# configure:2792: result: yes
# configure:2804: checking for MONO_MODULE
# configure:2811: $PKG_CONFIG --exists --print-errors "mono >= 2.10.0"
# configure:2814: $? = 0
# configure:2828: $PKG_CONFIG --exists --print-errors "mono >= 2.10.0"
# configure:2831: $? = 0
# configure:2889: result: yes
# configure:2900: checking for gmcs
# configure:2931: result: no
# configure:2942: error: You need to install 'gmcs'
#
# ## ---------------- ##
# ## Cache variables. ##
# ## ---------------- ##
#
# ac_cv_build=x86_64-unknown-linux-gnu
# ac_cv_env_MONO_MODULE_CFLAGS_set=
# ac_cv_env_MONO_MODULE_CFLAGS_value=
# ac_cv_env_MONO_MODULE_LIBS_set=
# ac_cv_env_MONO_MODULE_LIBS_value=
# ac_cv_env_PKG_CONFIG_LIBDIR_set=
# ac_cv_env_PKG_CONFIG_LIBDIR_value=
# ac_cv_env_PKG_CONFIG_PATH_set=
# ac_cv_env_PKG_CONFIG_PATH_value=
# ac_cv_env_PKG_CONFIG_set=
# ac_cv_env_PKG_CONFIG_value=
# ac_cv_env_build_alias_set=
# ac_cv_env_build_alias_value=
# ac_cv_env_host_alias_set=
# ac_cv_env_host_alias_value=
# ac_cv_env_target_alias_set=
# ac_cv_env_target_alias_value=
# ac_cv_host=x86_64-unknown-linux-gnu
# ac_cv_path_GMCS=no
# ac_cv_path_ac_pt_PKG_CONFIG=/usr/sbin/pkg-config
# ac_cv_path_install='/usr/bin/install -c'
# ac_cv_path_mkdir=/usr/sbin/mkdir
# ac_cv_prog_AWK=gawk
# ac_cv_prog_make_make_set=yes
# ac_cv_target=x86_64-unknown-linux-gnu
# am_cv_make_support_nested_variables=yes
# pkg_cv_MONO_MODULE_CFLAGS=
# pkg_cv_MONO_MODULE_LIBS=
#
# ## ----------------- ##
# ## Output variables. ##
# ## ----------------- ##
#
# ACLOCAL='${SHELL} /tmp/xsp/src/xsp-3.0.11/missing aclocal-1.15'
# ACLOCAL_AMFLAGS='-I build/m4/shamrock -I build/m4/shave ${ACLOCAL_FLAGS}'
# AMTAR='$${TAR-tar}'
# AM_BACKSLASH='\'
# AM_DEFAULT_V='$(AM_DEFAULT_VERBOSITY)'
# AM_DEFAULT_VERBOSITY='1'
# AM_MAKEFLAGS=''
# AM_V='$(V)'
# AUTOCONF='${SHELL} /tmp/xsp/src/xsp-3.0.11/missing autoconf'
# AUTOHEADER='${SHELL} /tmp/xsp/src/xsp-3.0.11/missing autoheader'
# AUTOMAKE='${SHELL} /tmp/xsp/src/xsp-3.0.11/missing automake-1.15'
# AWK='gawk'
# BUILD_DOCS_FALSE=''
# BUILD_DOCS_TRUE=''
# CC=''
# CCAS=''
# CXX=''
# CYGPATH_W='echo'
# DEFS=''
# DMCS=''
# DOCDIR=''
# ECHO_C=''
# ECHO_N='-n'
# ECHO_T=''
# F77=''
# FC=''
# GACUTIL=''
# GACUTIL_FLAGS=''
# GMCS='no'
# INSTALL_DATA='${INSTALL} -m 644'
# INSTALL_PROGRAM='${INSTALL}'
# INSTALL_SCRIPT='${INSTALL}'
# INSTALL_STRIP_PROGRAM='$(install_sh) -c -s'
# LIBOBJS=''
# LIBS=''
# LTLIBOBJS=''
# MAINT=''
# MAINTAINER_MODE_FALSE='#'
# MAINTAINER_MODE_TRUE=''
# MAKEFLAGS=''
# MAKEINFO='${SHELL} /tmp/xsp/src/xsp-3.0.11/missing makeinfo'
# MCS=''
# MDOC=''
# MKDIR_P='/usr/sbin/mkdir -p'
# MONO=''
# MONO_MODULE_CFLAGS=''
# MONO_MODULE_LIBS=''
# NET_2_0_FALSE=''
# NET_2_0_TRUE=''
# NET_4_0_FALSE=''
# NET_4_0_TRUE=''
# OBJC=''
# PACKAGE='xsp'
# PACKAGE_BUGREPORT='http://bugzilla.xamarin.com/'
# PACKAGE_NAME='xsp'
# PACKAGE_STRING='xsp 3.0'
# PACKAGE_TARNAME='xsp'
# PACKAGE_URL=''
# PACKAGE_VERSION='3.0'
# PATH_SEPARATOR=':'
# PKG_CONFIG='/usr/sbin/pkg-config'
# PKG_CONFIG_LIBDIR=''
# PKG_CONFIG_PATH=''
# PLATFORM_WIN32_FALSE=''
# PLATFORM_WIN32_TRUE=''
# Q=''
# RC=''
# RUNTIME=''
# SED=''
# SET_MAKE=''
# SHELL='/bin/sh'
# SN=''
# STRIP=''
# UNITTESTS_FALSE=''
# UNITTESTS_TRUE=''
# USE_SQLITE_FALSE=''
# USE_SQLITE_TRUE=''
# V=''
# VERSION='3.0'
# WEBTRACING=''
# XSP_ONLY_FALSE=''
# XSP_ONLY_TRUE=''
# XSP_VERSION=''
# am__isrc=''
# am__leading_dot='.'
# am__tar='$${TAR-tar} chof - "$$tardir"'
# am__untar='$${TAR-tar} xf -'
# bindir='${exec_prefix}/bin'
# build='x86_64-unknown-linux-gnu'
# build_alias=''
# build_cpu='x86_64'
# build_os='linux-gnu'
# build_vendor='unknown'
# datadir='${datarootdir}'
# datarootdir='${prefix}/share'
# docdir='${datarootdir}/doc/${PACKAGE_TARNAME}'
# dvidir='${docdir}'
# exec_prefix='/usr/local'
# expanded_bindir='/usr/local/bin'
# expanded_datadir='/usr/local/share'
# expanded_libdir='/usr/local/lib'
# host='x86_64-unknown-linux-gnu'
# host_alias=''
# host_cpu='x86_64'
# host_os='linux-gnu'
# host_vendor='unknown'
# htmldir='${docdir}'
# includedir='${prefix}/include'
# infodir='${datarootdir}/info'
# install_sh='${SHELL} /tmp/xsp/src/xsp-3.0.11/install-sh'
# libdir='${exec_prefix}/lib'
# libexecdir='${exec_prefix}/libexec'
# localedir='${datarootdir}/locale'
# localstatedir='${prefix}/var'
# mandir='${datarootdir}/man'
# mkdir_p='$(MKDIR_P)'
# oldincludedir='/usr/include'
# pdfdir='${docdir}'
# prefix='/usr/local'
# program_transform_name='s,x,x,'
# psdir='${docdir}'
# sbindir='${exec_prefix}/sbin'
# sharedstatedir='${prefix}/com'
# shavedir=''
# sysconfdir='${prefix}/etc'
# target='x86_64-unknown-linux-gnu'
# target_alias=''
# target_cpu='x86_64'
# target_os='linux-gnu'
# target_vendor='unknown'
#
# ## ----------- ##
# ## confdefs.h. ##
# ## ----------- ##
#
# /* confdefs.h */
# #define PACKAGE_NAME "xsp"
# #define PACKAGE_TARNAME "xsp"
# #define PACKAGE_VERSION "3.0"
# #define PACKAGE_STRING "xsp 3.0"
# #define PACKAGE_BUGREPORT "http://bugzilla.xamarin.com/"
# #define PACKAGE_URL ""
# #define PACKAGE "xsp"
# #define VERSION "3.0"
#
# configure: exit 1