The build took 00h 00m 47s and was NOT successful.
The program in this build is written in the following languages, according to sloccount:
| SLOC | Language | 
|---|---|
| 57,577 | ansic | 
| 2,982 | sh | 
| 28 | makefile | 
| 60,587 | total | 
The process tree of the build process is here.
    To avoid scrolling, you may jump to the last line of the
    invocation of makepkg that was used to build this
    package.
    
Removed vanilla repositories from pacman.conf and added:
        There were existing files in /sysroot, using those
        CMD: sudo -u tuscan PATH=/sysroot/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin CC=clang CXX=clang++ red makepkg --noextract --syncdeps --skipinteg --skippgpcheck --skipchecksums --noconfirm --nocolor --log --noprogressbar --nocheck
        ==> Making package: nauty 26r5-1 (Wed Apr  5 00:05:36 UTC 2017)==> Checking runtime dependencies...==> Checking buildtime dependencies...==> WARNING: Using existing $srcdir/ tree==> Starting build()...checking build system type... x86_64-pc-linux-gnuchecking host system type... x86_64-pc-linux-gnuchecking for gcc... clangchecking whether the C compiler works... yeschecking for C compiler default output file name... a.outchecking for suffix of executables... checking whether we are cross compiling... configure: error: in `/tmp/nauty/src/nauty26r5':configure: error: cannot run C compiled programs.If you meant to cross compile, use `--host'.See `config.log' for more details==> ERROR: A failure occurred in build().    Aborting...Printing config logfiles
        CMD: config logfiles '/tmp/nauty/src/nauty26r5/config.log'
        This file contains any messages produced by compilers whilerunning configure, to aid debugging if configure makes a mistake.It was created by configure, which wasgenerated by GNU Autoconf 2.69.  Invocation command line was$ ./configure## --------- #### Platform. #### --------- ##hostname = f50f49368a4cuname -m = x86_64uname -r = 4.10.6-1-ARCHuname -s = Linuxuname -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          = unknownPATH: /sysroot/binPATH: /usr/local/sbinPATH: /usr/local/binPATH: /usr/sbinPATH: /usr/binPATH: /sbinPATH: /bin## ----------- #### Core tests. #### ----------- ##configure:2447: checking build system typeconfigure:2461: result: x86_64-pc-linux-gnuconfigure:2481: checking host system typeconfigure:2494: result: x86_64-pc-linux-gnuconfigure:2564: checking for gccconfigure:2591: result: clangconfigure:2820: checking for C compiler versionconfigure:2829: clang --version >&5clang version 3.8.1Target: x86_64-unknown-linux-gnuThread model: posixInstalledDir: /configure:2840: $? = 0configure:2829: clang -v >&5clang version 3.8.1Target: x86_64-unknown-linux-gnuThread model: posixInstalledDir: /Found candidate GCC installation: //../lib/gcc/x86_64-pc-linux-gnu/6.1.1Found candidate GCC installation: //../lib64/gcc/x86_64-pc-linux-gnu/6.1.1Selected GCC installation: //../lib64/gcc/x86_64-pc-linux-gnu/6.1.1Candidate multilib: .;@m64Selected multilib: .;@m64configure:2840: $? = 0configure:2829: clang -V >&5clang-3.8: error: argument to '-V' is missing (expected 1 value)clang-3.8: error: no input filesconfigure:2840: $? = 1configure:2829: clang -qversion >&5clang-3.8: error: unknown argument: '-qversion'clang-3.8: error: no input filesconfigure:2840: $? = 1configure:2860: checking whether the C compiler worksconfigure:2882: clang    conftest.c  >&5configure:2886: $? = 0configure:2934: result: yesconfigure:2937: checking for C compiler default output file nameconfigure:2939: result: a.outconfigure:2945: checking for suffix of executablesconfigure:2952: clang -o conftest    conftest.c  >&5configure:2956: $? = 0configure:2978: result:configure:3000: checking whether we are cross compilingconfigure:3008: clang -o conftest    conftest.c  >&5configure:3012: $? = 0configure:3019: ./conftest./conftest: error while loading shared libraries: /usr/lib/libc.so: invalid ELF headerconfigure:3023: $? = 127configure:3030: error: in `/tmp/nauty/src/nauty26r5':configure:3032: error: cannot run C compiled programs.If you meant to cross compile, use `--host'.See `config.log' for more details## ---------------- #### Cache variables. #### ---------------- ##ac_cv_build=x86_64-pc-linux-gnuac_cv_env_CC_set=setac_cv_env_CC_value=clangac_cv_env_CFLAGS_set=setac_cv_env_CFLAGS_value=ac_cv_env_CPPFLAGS_set=setac_cv_env_CPPFLAGS_value=ac_cv_env_CPP_set=ac_cv_env_CPP_value=ac_cv_env_LDFLAGS_set=setac_cv_env_LDFLAGS_value=ac_cv_env_LIBS_set=ac_cv_env_LIBS_value=ac_cv_env_build_alias_set=ac_cv_env_build_alias_value=ac_cv_env_host_alias_set=ac_cv_env_host_alias_value=ac_cv_env_target_alias_set=ac_cv_env_target_alias_value=ac_cv_host=x86_64-pc-linux-gnuac_cv_prog_ac_ct_CC=clang## ----------------- #### Output variables. #### ----------------- ##CC='clang'CFLAGS=''CPP=''CPPFLAGS=''DEFS=''ECHO_C=''ECHO_N='-n'ECHO_T=''EGREP=''EXEEXT=''GREP=''LDFLAGS=''LIBOBJS=''LIBS=''LTLIBOBJS=''MORECFLAGS=''OBJEXT=''PACKAGE_BUGREPORT=''PACKAGE_NAME=''PACKAGE_STRING=''PACKAGE_TARNAME=''PACKAGE_URL=''PACKAGE_VERSION=''PATH_SEPARATOR=':'SHELL='/bin/sh'ac_ct_CC='clang'ac_cv_sizeof___int128_t=''ac_cv_sizeof_int=''ac_cv_sizeof_long=''ac_cv_sizeof_long_long=''ac_cv_sys_file_offset_bits=''ac_cv_tls=''allow_interrupt=''bindir='${exec_prefix}/bin'build='x86_64-pc-linux-gnu'build_alias=''build_cpu='x86_64'build_os='linux-gnu'build_vendor='pc'datadir='${datarootdir}'datarootdir='${prefix}/share'default_wordsize=''docdir='${datarootdir}/doc/${PACKAGE}'dvidir='${docdir}'edit_msg=''exec_prefix='NONE'fdopen_dec=''ftell_dec=''has_math_inf=''have_ansicontrols=''have_clz=''have_clzl=''have_clzll=''have_const=''have_fork=''have_fseeko=''have_getrusage=''have_gettimeofday=''have_hwpopcnt=''have_isatty=''have_mmpop32=''have_mmpop64=''have_perror=''have_pid_t=''have_pipe=''have_popcnt=''have_popcntl=''have_popcntll=''have_popen=''have_pthread=''have_putenv=''have_setenv=''have_sigaction=''have_sigprocmask=''have_time=''have_times=''have_tls=''have_wait=''header_errno_h=''header_pthread_h=''header_signal_h=''header_stddef_h=''header_stdlib_h=''header_string_h=''header_sys_types_h=''header_sys_wait_h=''header_unistd_h=''host='x86_64-pc-linux-gnu'host_alias=''host_cpu='x86_64'host_os='linux-gnu'host_vendor='pc'htmldir='${docdir}'includedir='${prefix}/include'infodir='${datarootdir}/info'libdir='${exec_prefix}/lib'libexecdir='${exec_prefix}/libexec'localedir='${datarootdir}/locale'localstatedir='${prefix}/var'lok=''malloc_dec=''mandir='${datarootdir}/man'oldincludedir='/usr/include'pdfdir='${docdir}'popen_dec=''prefix='NONE'program_transform_name='s,x,x,'psdir='${docdir}'putenv_dec=''sbindir='${exec_prefix}/sbin'setenv_dec=''sharedstatedir='${prefix}/com'shortg_or_null=''sort_newparams_ok=''sort_prog=''stdio_nolock=''sysconfdir='${prefix}/etc'target_alias=''testprogs=''threadlib=''## ----------- #### 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