dnl === configure.ac --------------------------------------------------------=== dnl The LLVM Compiler Infrastructure dnl dnl This file was developed by the LLVM research group and is distributed under dnl the University of Illinois Open Source License. See LICENSE.TXT for details. dnl dnl===-----------------------------------------------------------------------=== dnl This is the LLVM configuration script. It is processed by the autoconf dnl program to produce a script named configure. This script contains the dnl configuration checks that LLVM needs in order to support multiple platforms. dnl This file is composed of 10 sections per the recommended organization of dnl autoconf input defined in the autoconf documentation. As this file evolves, dnl please keep the various types of checks within their sections. The sections dnl are as follows: dnl dnl SECTION 1: Initialization & Setup dnl SECTION 2: Architecture, target, and host checks dnl SECTION 3: Command line arguments for the configure script. dnl SECTION 4: Check for programs we need and that they are the right version dnl SECTION 5: Check for libraries dnl SECTION 6: Check for header files dnl SECTION 7: Check for types and structures dnl SECTION 8: Check for specific functions needed dnl SECTION 9: Additional checks, variables, etc. dnl SECTION 10: Specify the output files and generate it dnl dnl===-----------------------------------------------------------------------=== dnl=== dnl=== SECTION 1: Initialization & Setup dnl=== dnl===-----------------------------------------------------------------------=== dnl Initialize autoconf and define the package name, version number and dnl email address for reporting bugs. AC_INIT([[llvm]],[[1.4]],[llvmbugs@cs.uiuc.edu]) dnl Provide a copyright substitution and ensure the copyright notice is included dnl in the output of --version option of the generated configure script. AC_SUBST(LLVM_COPYRIGHT,["Copyright (c) 2003-2005 U University of Illinois at Urbana-Champaign."]) AC_COPYRIGHT($LLVM_COPYRIGHT) dnl Indicate that we require autoconf 2.59 or later. Ths is needed because we dnl use some autoconf macros only available in 2.59. AC_PREREQ(2.59) dnl Verify that the source directory is valid. This makes sure that we are dnl configuring LLVM and not some other package (it validates --srcdir argument) AC_CONFIG_SRCDIR([lib/VMCore/Module.cpp]) dnl Place all of the extra autoconf files into the config subdirectory. Tell dnl various tools where the m4 autoconf macros are. AC_CONFIG_AUX_DIR([autoconf]) dnl Quit if the source directory has already been configured. dnl NOTE: This relies upon undocumented autoconf behavior. if test ${srcdir} != "." ; then if test -f ${srcdir}/include/llvm/Config/config.h ; then AC_MSG_ERROR([Already configured in ${srcdir}]) fi fi dnl Configure all of the projects present in our source tree. While we could dnl just AC_CONFIG_SUBDIRS on the set of directories in projects that have a dnl configure script, that usage of the AC_CONFIG_SUBDIRS macro is deprecated. dnl Instead we match on the known projects. for i in `ls ${srcdir}/projects` do if test -d ${srcdir}/projects/${i} ; then case ${i} in "CVS") ;; "sample") AC_CONFIG_SUBDIRS([projects/sample]) ;; "Stacker") AC_CONFIG_SUBDIRS([projects/Stacker]) ;; "llvm-test") AC_CONFIG_SUBDIRS([projects/llvm-test]) ;; "llvm-reopt") AC_CONFIG_SUBDIRS([projects/llvm-reopt]);; "llvm-gcc") AC_CONFIG_SUBDIRS([projects/llvm-gcc]) ;; "Java") AC_CONFIG_SUBDIRS([projects/Java]) ;; "llvm-tv") AC_CONFIG_SUBDIRS([projects/llvm-tv]) ;; "llvm-fefw") AC_CONFIG_SUBDIRS([projects/llvm-fefw]) ;; "poolalloc") AC_CONFIG_SUBDIRS([projects/poolalloc]) ;; *) AC_MSG_WARN([Unknown project (${i}) won't be configured automatically]) ;; esac fi done dnl===-----------------------------------------------------------------------=== dnl=== dnl=== SECTION 2: Architecture, target, and host checks dnl=== dnl===-----------------------------------------------------------------------=== dnl Check the target for which we're compiling and the host that will do the dnl compilations. This will tell us which LLVM compiler will be used for dnl compiling SSA into object code. This needs to be done early because dnl following tests depend on it. AC_CANONICAL_TARGET dnl Determine the platform type and cache its value. This helps us configure dnl the System library to the correct build platform. AC_CACHE_CHECK([type of operating system we're on], [llvm_cv_os_type], [case $build in *-*-aix*) llvm_cv_os_type="AIX" llvm_cv_platform_type="Unix" ;; *-*-cygwin*) llvm_cv_os_type="Cygwin" llvm_cv_platform_type="Unix" ;; *-*-darwin*) llvm_cv_os_type="Darwin" llvm_cv_platform_type="Unix" ;; *-*-freebsd*) llvm_cv_os_type="FreeBSD" llvm_cv_platform_type="Unix" ;; *-*-interix*) llvm_cv_os_type="Interix" llvm_cv_platform_type="Unix" ;; *-*-linux*) llvm_cv_os_type="Linux" llvm_cv_platform_type="Unix" ;; *-*-solaris*) llvm_cv_os_type="SunOS" llvm_cv_platform_type="Unix" ;; *-*-win32*) llvm_cv_os_type="Win32" llvm_cv_platform_type="Win32" ;; *-*-mingw*) llvm_cv_os_type="MingW" llvm_cv_platform_type="Win32" ;; *) llvm_cv_os_type="Unknown" llvm_cv_platform_type="Unknown" ;; esac]) dnl Make sure we aren't attempting to configure for an unknown system if test "$llvm_cv_os_type" = "Unknown" ; then AC_MSG_ERROR([Operating system is unknown, configure can't continue]) fi dnl Set the "OS" Makefile variable based on the platform type so the dnl makefile can configure itself to specific build hosts AC_SUBST(OS,$llvm_cv_os_type) dnl Set the "LLVM_ON_*" variables based on llvm_cvs_platform_type dnl This is used by lib/System to determine the basic kind of implementation dnl to use. case $llvm_cv_platform_type in Unix) AC_DEFINE([LLVM_ON_UNIX],[1],[Define if this is Unixish platform]) ;; Win32) AC_DEFINE([LLVM_ON_WIN32],[1],[Define if this is Win32ish platform]) ;; esac dnl Make a link from lib/System/platform to lib/System/$llvm_cv_os_type dnl This helps the #inclusion of the system specific include files dnl for the operating system abstraction library, lib/System. AC_CONFIG_LINKS(lib/System/platform:lib/System/$llvm_cv_os_type) dnl If we are targetting a Sparc machine running Solaris, pretend that it is dnl V9, since that is all that we support at the moment, and autoconf will only dnl tell us we're a sparc. case $target in sparc*-*-solaris*) AC_SUBST(target,[[sparcv9-sun-solaris2.8]]) ;; esac dnl Determine what our target architecture is and configure accordingly. dnl This will allow Makefiles to make a distinction between the hardware and dnl the OS. AC_CACHE_CHECK([target architecture],[llvm_cv_target_arch], [case $target in i?86-*) llvm_cv_target_arch="x86" ;; amd64-* | x86_64-*) llvm_cv_target_arch="AMD64" ;; sparc*-*) llvm_cv_target_arch="Sparc" ;; powerpc*-*) llvm_cv_target_arch="PowerPC" ;; *) llvm_cv_target_arch="Unknown" ;; esac]) if test "$llvm_cv_target_arch" = "Unknown" ; then AC_MSG_WARN([Configuring LLVM for an unknown target archicture]) fi dnl Define a substitution, ARCH, for the target architecture AC_SUBST(ARCH,$llvm_cv_target_arch) dnl Check for the endianness of the target AC_C_BIGENDIAN(AC_SUBST([ENDIAN],[big]),AC_SUBST([ENDIAN],[little])) dnl===-----------------------------------------------------------------------=== dnl=== dnl=== SECTION 3: Command line arguments for the configure script. dnl=== dnl===-----------------------------------------------------------------------=== dnl --enable-optimized : check whether they want to do an optimized build: AC_ARG_ENABLE(optimized, AS_HELP_STRING([--enable-optimized,Compile with optimizations enabled (default is NO)]),,enableval=no) if test ${enableval} = "no" ; then AC_SUBST(ENABLE_OPTIMIZED,[[]]) else AC_SUBST(ENABLE_OPTIMIZED,[[ENABLE_OPTIMIZED=1]]) fi dnl --enable-jit: check whether they want to enable the jit AC_ARG_ENABLE(jit, AS_HELP_STRING(--enable-jit, [Enable Just In Time Compiling (default is YES)]),, enableval=default) if test ${enableval} = "no" then AC_SUBST(JIT,[[]]) else case "$llvm_cv_target_arch" in x86) AC_SUBST(JIT,[[TARGET_HAS_JIT=1]]) ;; Sparc) AC_SUBST(JIT,[[TARGET_HAS_JIT=1]]) ;; PowerPC) AC_SUBST(JIT,[[TARGET_HAS_JIT=1]]) ;; AMD64) AC_SUBST(JIT,[[]]) ;; *) AC_SUBST(JIT,[[]]) ;; esac fi dnl Allow enablement of doxygen generated documentation AC_ARG_ENABLE(doxygen, AS_HELP_STRING([--enable-doxygen], [Build doxygen documentation (default is NO)]),, enableval=default) case "$enableval" in yes) AC_SUBST(ENABLE_DOXYGEN,[1]) ;; no) AC_SUBST(ENABLE_DOXYGEN,[0]) ;; default) AC_SUBST(ENABLE_DOXYGEN,[0]) ;; *) AC_MSG_ERROR([Invalid setting for --enable-doxygen. Use "yes" or "no"]) ;; esac dnl Allow a specific llvm-gcc/llvm-g++ pair to be used with this LLVM config. AC_ARG_WITH(llvmgccdir, AS_HELP_STRING([--with-llvmgccdir], [Specify location of llvm-gcc install dir (default searches PATH)]),, withval=default) case "$withval" in default) WITH_LLVMGCCDIR=default ;; /*) WITH_LLVMGCCDIR=$withval ;; *) AC_MSG_ERROR([Invalid path for --with-llvmgccdir. Provide full path]) ;; esac dnl===-----------------------------------------------------------------------=== dnl=== dnl=== SECTION 4: Check for programs we need and that they are the right version dnl=== dnl===-----------------------------------------------------------------------=== dnl Check for compilation tools AC_PROG_CPP AC_PROG_CC(gcc) AC_PROG_CXX(g++) AC_PROG_FLEX AC_PROG_BISON dnl Check for the tools that the makefiles require AC_CHECK_GNU_MAKE AC_PROG_LN_S AC_PATH_PROG(CMP, [cmp], [cmp]) AC_PATH_PROG(CP, [cp], [cp]) AC_PATH_PROG(DATE, [date], [date]) AC_PATH_PROG(FIND, [find], [find]) AC_PATH_PROG(GREP, [grep], [grep]) AC_PATH_PROG(MKDIR,[mkdir],[mkdir]) AC_PATH_PROG(MV, [mv], [mv]) AC_PATH_PROG(PAX, [pax], [pax]) AC_PROG_RANLIB AC_PATH_PROG(RM, [rm], [rm]) AC_PATH_PROG(SED, [sed], [sed]) AC_PATH_PROG(TAR, [tar], [gtar]) dnl Find the install program AC_PROG_INSTALL dnl Checks for documentation and testing tools that we can do without. If these dnl are not found then they are set to "true" which always succeeds but does dnl nothing. This just lets the build output show that we could have done dnl something if the tool was available. AC_PATH_PROG(BZIP2,[bzip2],[true bzip2]) AC_PATH_PROG(DOT,[dot],[true dot]) AC_PATH_PROG(DOXYGEN,[doxygen],[true doxygen]) AC_PATH_PROG(ETAGS,[etags],[true etags]) AC_PATH_PROG(GROFF,[groff],[true groff]) AC_PATH_PROG(GZIP,[gzip],[true gzip]) AC_PATH_PROG(POD2HTML,[pod2html],[true pod2html]) AC_PATH_PROG(POD2MAN,[pod2man],[true pod2man]) AC_PATH_PROG(RUNTEST,[runtest],[true runtest]) DJ_AC_PATH_TCLSH AC_PATH_PROG(ZIP,[zip],[true zip]) dnl Determine if the linker supports the -R option. AC_LINK_USE_R dnl Check for libtool and the library that has dlopen function (which must come dnl before the AC_PROG_LIBTOOL check in order to enable dlopening libraries with dnl libtool). AC_LIBTOOL_DLOPEN AC_LIB_LTDL AC_PROG_LIBTOOL dnl Check if we know how to tell etags we are using C++: etags_version=`$ETAGS --version 2>&1` case "$etags_version" in *[Ee]xuberant*) ETAGSFLAGS="--language-force=c++" ;; *GNU\ Emacs*) ETAGSFLAGS="-l c++" ;; *) ETAGSFLAGS="" ;; esac AC_SUBST(ETAGSFLAGS,$ETAGSFLAGS) if test "$WITH_LLVMGCCDIR" = "default" ; then AC_PATH_PROG(LLVMGCC, [llvm-gcc], [llvm-gcc]) AC_PATH_PROG(LLVMGXX, [llvm-g++], [llvm-g++]) else LLVMGCC=$WITH_LLVMGCCDIR/bin/llvm-gcc LLVMGXX=$WITH_LLVMGCCDIR/bin/llvm-g++ AC_SUBST(LLVMGCC,$LLVMGCC) AC_SUBST(LLVMGXX,$LLVMGXX) fi AC_MSG_CHECKING([tool compatibility]) dnl Ensure that compilation tools are GCC or a GNU compatible compiler such as dnl ICC; we use GCC specific options in the makefiles so the compiler needs dnl to support those options. dnl "icc" emits gcc signatures dnl "icc -no-gcc" emits no gcc signature BUT is still compatible ICC=no IXX=no case $CC in icc*|icpc*) ICC=yes IXX=yes ;; *) ;; esac if test "$GCC" != "yes" && test "$ICC" != "yes" then AC_MSG_ERROR([gcc|icc required but not found]) fi dnl Ensure that compilation tools are GCC; we use GCC specific extensions if test "$GXX" != "yes" && test "$IXX" != "yes" then AC_MSG_ERROR([g++|icc required but not found]) fi dnl Verify that GCC is version 3.0 or higher if test "$GCC" = "yes" then gccmajor=`$CC --version | head -n 1 | awk '{print $NF;}' | cut -d. -f1` if test "$gccmajor" -lt "3" then AC_MSG_ERROR([gcc 3.x required, but you have a lower version]) fi fi dnl Check for GNU Make. We use its extensions, so don't build without it if test -z "$llvm_cv_gnu_make_command" then AC_MSG_ERROR([GNU Make required but not found]) fi dnl Tool compatibility is okay if we make it here. AC_MSG_RESULT([ok]) dnl===-----------------------------------------------------------------------=== dnl=== dnl=== SECTION 5: Check for libraries dnl=== dnl===-----------------------------------------------------------------------=== dnl libelf is for sparc only; we can ignore it if we don't have it AC_CHECK_LIB(elf, elf_begin) dnl lt_dlopen may be required for plugin support. AC_SEARCH_LIBS(lt_dlopen,ltdl,AC_DEFINE([HAVE_LT_DLOPEN],[1], [Define if lt_dlopen() is available on this platform]), AC_MSG_WARN([lt_dlopen() not found - plugin support might not be available])) dnl dlopen() is required for plugin support. AC_SEARCH_LIBS(dlopen,dl,AC_DEFINE([HAVE_DLOPEN],[1], [Define if dlopen() is available on this platform.]), AC_MSG_WARN([dlopen() not found - disabling plugin support])) dnl mallinfo is optional; the code can compile (minus features) without it AC_SEARCH_LIBS(mallinfo,malloc,AC_DEFINE([HAVE_MALLINFO],[1], [Define if mallinfo() is available on this platform.])) dnl pthread locking functions are optional - but llvm will not be thread-safe dnl without locks. AC_SEARCH_LIBS(pthread_mutex_lock,pthread, AC_DEFINE([HAVE_PTHREAD_MUTEX_LOCK],[1], [Have pthread_mutex_lock])) dnl===-----------------------------------------------------------------------=== dnl=== dnl=== SECTION 6: Check for header files dnl=== dnl===-----------------------------------------------------------------------=== dnl First, use autoconf provided macros for specific headers that we need dnl We don't check for ancient stuff or things that are guaranteed to be there dnl by the C++ standard. We always use the versions of C headers. dnl Generally we're looking for POSIX headers. AC_HEADER_DIRENT AC_HEADER_MMAP_ANONYMOUS AC_HEADER_STAT AC_HEADER_STDC AC_HEADER_SYS_WAIT AC_HEADER_TIME AC_CHECK_HEADERS([dlfcn.h execinfo.h fcntl.h inttypes.h limits.h link.h]) AC_CHECK_HEADERS([malloc.h signal.h stdint.h unistd.h utime.h windows.h]) AC_CHECK_HEADERS([sys/mman.h sys/param.h sys/resource.h sys/time.h sys/types.h]) dnl===-----------------------------------------------------------------------=== dnl=== dnl=== SECTION 7: Check for types and structures dnl=== dnl===-----------------------------------------------------------------------=== AC_TYPE_PID_T AC_TYPE_SIZE_T AC_TYPE_SIGNAL AC_STRUCT_TM AC_CHECK_TYPES([int64_t],,AC_MSG_ERROR([Type int64_t required but not found])) AC_CHECK_TYPES([uint64_t],, AC_CHECK_TYPES([u_int64_t],, AC_MSG_ERROR([Type uint64_t or u_int64_t required but not found]))) dnl===-----------------------------------------------------------------------=== dnl=== dnl=== SECTION 8: Check for specific functions needed dnl=== dnl===-----------------------------------------------------------------------=== AC_CHECK_FUNCS([backtrace getcwd getpagesize getrusage gettimeofday isatty ]) AC_CHECK_FUNCS([mkdtemp mkstemp mktemp ]) AC_CHECK_FUNCS([realpath setrlimit strdup strtoq strtoll sysconf ]) AC_C_PRINTF_A AC_FUNC_ALLOCA AC_FUNC_RAND48 dnl Check for variations in the Standard C++ library and STL. These macros are dnl provided by LLVM in the autoconf/m4 directory. AC_CXX_HAVE_HASH_MAP AC_CXX_HAVE_HASH_SET AC_CXX_HAVE_STD_ITERATOR AC_CXX_HAVE_BI_ITERATOR AC_CXX_HAVE_FWD_ITERATOR AC_FUNC_ISNAN AC_FUNC_ISINF dnl Check for mmap and mprotect support. We need both to do the JIT and for dnl bytecode loading, etc. AC_FUNC_MMAP AC_FUNC_MMAP_FILE AC_CHECK_FUNC(mprotect,, AC_MSG_ERROR([Function mprotect() required but not found])) if test "$ac_cv_func_mmap_fixed_mapped" = "no" then AC_MSG_WARN([mmap() required but not found]) fi if test "$ac_cv_func_mmap_file" = "no" then AC_MSG_WARN([mmap() of files required but not found]) fi dnl===-----------------------------------------------------------------------=== dnl=== dnl=== SECTION 9: Additional checks, variables, etc. dnl=== dnl===-----------------------------------------------------------------------=== dnl See if the llvm-gcc executable can compile to LLVM assembly AC_CACHE_CHECK([whether llvm-gcc is sane],[llvm_cv_llvmgcc_sanity], [llvm_cv_llvmgcc_sanity="no" if test -x "$LLVMGCC" ; then cp /dev/null conftest.c "$LLVMGCC" -S -o - conftest.c | grep implementation > /dev/null 2>&1 if test $? -eq 0 ; then llvm_cv_llvmgcc_sanity="yes" fi rm conftest.c fi]) dnl Since we have a sane llvm-gcc, identify it and its sub-tools if test "$llvm_cv_llvmgcc_sanity" = "yes" ; then llvmcc1path=`"$LLVMGCC" --print-prog-name=cc1` AC_SUBST(LLVMCC1,$llvmcc1path) llvmcc1pluspath=`"$LLVMGCC" --print-prog-name=cc1plus` AC_SUBST(LLVMCC1PLUS,$llvmcc1pluspath) llvmgccdir=`echo "$llvmcc1path" | sed 's,/libexec/.*,,'` AC_SUBST(LLVMGCCDIR,$llvmgccdir) fi dnl Propagate the shared library extension that the libltdl checks did to dnl the Makefiles so we can use it there too AC_SUBST(SHLIBEXT,$libltdl_cv_shlibext) # Translate the various configuration directories and other basic # information into substitutions that will end up in Makefile.config.in # that these configured values can be used by the makefiles eval LLVM_PREFIX="${prefix}"; eval LLVM_BINDIR="${prefix}/bin"; eval LLVM_LIBDIR="${prefix}/lib"; eval LLVM_DATADIR="${prefix}/share/llvm"; eval LLVM_DOCSDIR="${prefix}/docs/llvm"; eval LLVM_ETCDIR="${prefix}/etc/llvm"; eval LLVM_INCLUDEDIR="${prefix}/include"; eval LLVM_INFODIR="${prefix}/info"; eval LLVM_MANDIR="${prefix}/man"; LLVM_CONFIGTIME=`date` AC_SUBST(LLVM_PREFIX) AC_SUBST(LLVM_BINDIR) AC_SUBST(LLVM_LIBDIR) AC_SUBST(LLVM_DATADIR) AC_SUBST(LLVM_DOCSDIR) AC_SUBST(LLVM_ETCDIR) AC_SUBST(LLVM_INCLUDEDIR) AC_SUBST(LLVM_INFODIR) AC_SUBST(LLVM_MANDIR) AC_SUBST(LLVM_CONFIGTIME) # Place the various directores into the config.h file as #defines so that we # can know about the installation paths within LLVM. AC_DEFINE_UNQUOTED(LLVM_PREFIX,"$LLVM_PREFIX", [Installation prefix directory]) AC_DEFINE_UNQUOTED(LLVM_BINDIR, "$LLVM_BINDIR", [Installation directory for binary executables]) AC_DEFINE_UNQUOTED(LLVM_LIBDIR, "$LLVM_LIBDIR", [Installation directory for libraries]) AC_DEFINE_UNQUOTED(LLVM_DATADIR, "$LLVM_DATADIR", [Installation directory for data files]) AC_DEFINE_UNQUOTED(LLVM_DATADIR, "$LLVM_DOCSDIR", [Installation directory for documentation]) AC_DEFINE_UNQUOTED(LLVM_ETCDIR, "$LLVM_ETCDIR", [Installation directory for config files]) AC_DEFINE_UNQUOTED(LLVM_INCLUDEDIR, "$LLVM_INCLUDEDIR", [Installation directory for include files]) AC_DEFINE_UNQUOTED(LLVM_INFODIR, "$LLVM_INFODIR", [Installation directory for .info files]) AC_DEFINE_UNQUOTED(LLVM_MANDIR, "$LLVM_MANDIR", [Installation directory for man pages]) AC_DEFINE_UNQUOTED(LLVM_CONFIGTIME, "$LLVM_CONFIGTIME", [Time at which LLVM was configured]) dnl===-----------------------------------------------------------------------=== dnl=== dnl=== SECTION 10: Specify the output files and generate it dnl=== dnl===-----------------------------------------------------------------------=== dnl Configure header files AC_CONFIG_HEADERS(include/llvm/Config/config.h) AC_CONFIG_HEADERS([include/llvm/Support/DataTypes.h]) AC_CONFIG_HEADERS([include/llvm/ADT/hash_map]) AC_CONFIG_HEADERS([include/llvm/ADT/hash_set]) AC_CONFIG_HEADERS([include/llvm/Support/ThreadSupport.h]) AC_CONFIG_HEADERS([include/llvm/ADT/iterator]) dnl Configure the makefile's configuration data AC_CONFIG_FILES([Makefile.config]) dnl Configure llvmc's configuration files AC_CONFIG_FILES([tools/llvmc/st tools/llvmc/cpp tools/llvmc/ll tools/llvmc/c]) dnl Configure doxygen's configuration file AC_CONFIG_FILES([docs/doxygen.cfg]) dnl Do special configuration of Makefiles AC_CONFIG_MAKEFILE(Makefile) AC_CONFIG_MAKEFILE(Makefile.common) AC_CONFIG_MAKEFILE(examples/Makefile) AC_CONFIG_MAKEFILE(lib/Makefile) AC_CONFIG_MAKEFILE(runtime/Makefile) AC_CONFIG_MAKEFILE(test/Makefile) AC_CONFIG_MAKEFILE(test/Makefile.tests) AC_CONFIG_MAKEFILE(tools/Makefile) AC_CONFIG_MAKEFILE(utils/Makefile) AC_CONFIG_MAKEFILE(projects/Makefile) dnl Finally, crank out the output AC_OUTPUT dnl Warn loudly if llvm-gcc was not obviously working if test "$llvm_cv_llvmgcc_sanity" = "no" ; then AC_MSG_WARN([***** llvm-gcc/llvm-g++ was not found, or does not appear to be ]) AC_MSG_WARN([***** working. Please make sure you have llvmgcc and llvmg++ in]) AC_MSG_WARN([***** your path before configuring LLVM. The runtime libraries]) AC_MSG_WARN([***** (llvm/runtime) will not be built but you should be able to]) AC_MSG_WARN([***** build the llvm tools.]) fi