AC_MSG_CHECKING([whether GCC or Clang is our host compiler])
AC_LANG_PUSH([C++])
llvm_cv_cxx_compiler=unknown
-AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#if ! __clang__
- #error
- #endif
- ]])],
+AC_COMPILE_IFELSE([AC_LANG_SOURCE([[#if ! __clang__
+ #error
+ #endif
+ ]])],
llvm_cv_cxx_compiler=clang,
- [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#if ! __GNUC__
- #error
- #endif
- ]])],
+ [AC_COMPILE_IFELSE([AC_LANG_SOURCE([[#if ! __GNUC__
+ #error
+ #endif
+ ]])],
llvm_cv_cxx_compiler=gcc, [])])
AC_LANG_POP([C++])
AC_MSG_RESULT([${llvm_cv_cxx_compiler}])
-dnl Check both GCC and Clang for sufficiently modern versions. These checks can
-dnl be bypassed by passing a flag if necessary on a platform.
-AC_ARG_ENABLE(compiler-version-checks,
- AS_HELP_STRING([--enable-compiler-version-checks],
- [Check the version of the host compiler (default is YES)]),,
- enableval=default)
-case "$enableval" in
- no)
- ;;
- yes|default)
- AC_LANG_PUSH([C++])
- case "$llvm_cv_cxx_compiler" in
- clang)
- AC_MSG_CHECKING([whether Clang is new enough])
- AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
-#if __clang_major__ < 3 || (__clang_major__ == 3 && __clang_minor__ < 1)
-#error This version of Clang is too old to build LLVM
-#endif
-]])],
- [AC_MSG_RESULT([yes])],
- [AC_MSG_RESULT([no])
- AC_MSG_ERROR([
-The selected Clang compiler is not new enough to build LLVM. Please upgrade to
-Clang 3.1. You may pass --disable-compiler-version-checks to configure to
-bypass these sanity checks.])])
- ;;
- gcc)
- AC_MSG_CHECKING([whether GCC is new enough])
- AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
-#if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 7)
-#error This version of GCC is too old to build LLVM
-#endif
-]])],
- [AC_MSG_RESULT([yes])],
- [AC_MSG_RESULT([no])
- AC_MSG_ERROR([
-The selected GCC C++ compiler is not new enough to build LLVM. Please upgrade
-to GCC 4.7. You may pass --disable-compiler-version-checks to configure to
-bypass these sanity checks.])])
- ;;
- unknown)
- ;;
- esac
- AC_LANG_POP([C++])
- ;;
- *)
- AC_MSG_ERROR([Invalid setting for --enable-compiler-version-checks. Use "yes" or "no"])
- ;;
-esac
-
dnl Configure all of the projects present in our source tree. While we could
dnl just AC_CONFIG_SUBDIRS on the set of directories in projects that have a
dnl configure script, that usage of the AC_CONFIG_SUBDIRS macro is deprecated.
*) AC_MSG_ERROR([Invalid setting for --enable-libcpp. Use "yes" or "no"]) ;;
esac
+dnl Check both GCC and Clang for sufficiently modern versions. These checks can
+dnl be bypassed by passing a flag if necessary on a platform. We have to do
+dnl these checks here so that we have the configuration of the standard C++
+dnl library finished.
+AC_ARG_ENABLE(compiler-version-checks,
+ AS_HELP_STRING([--enable-compiler-version-checks],
+ [Check the version of the host compiler (default is YES)]),,
+ enableval=default)
+case "$enableval" in
+ no)
+ ;;
+ yes|default)
+ AC_LANG_PUSH([C++])
+ case "$llvm_cv_cxx_compiler" in
+ clang)
+ AC_MSG_CHECKING([whether Clang is new enough])
+ AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
+#if __clang_major__ < 3 || (__clang_major__ == 3 && __clang_minor__ < 1)
+#error This version of Clang is too old to build LLVM
+#endif
+]])],
+ [AC_MSG_RESULT([yes])],
+ [AC_MSG_RESULT([no])
+ AC_MSG_ERROR([
+The selected Clang compiler is not new enough to build LLVM. Please upgrade to
+Clang 3.1. You may pass --disable-compiler-version-checks to configure to
+bypass these sanity checks.])])
+
+ dnl Note that libstdc++4.6 is known broken for C++11 builds. The errors
+ dnl are sometimes deeply confusing though. Here we test for an obvious
+ dnl incomplete feature in 4.6's standard library that was completed in
+ dnl 4.7's. We also have to disable this test if 'ENABLE_LIBCPP' is set
+ dnl because the enable flags don't actually fix CXXFLAGS, they rely on
+ dnl that happening in the Makefile.
+ if test "$ENABLE_LIBCPP" -eq 0 ; then
+ AC_MSG_CHECKING([whether Clang will select a modern C++ standard library])
+ llvm_cv_old_cxxflags="$CXXFLAGS"
+ CXXFLAGS="$CXXFLAGS -std=c++0x"
+ AC_LINK_IFELSE([AC_LANG_SOURCE([[
+#include <atomic>
+std::atomic<float> x(0.0f);
+int main() { return (float)x; }
+]])],
+ [AC_MSG_RESULT([yes])],
+ [AC_MSG_RESULT([no])
+ AC_MSG_ERROR([
+We detected a missing feature in the standard C++ library that was known to be
+missing in libstdc++4.6 and implemented in libstdc++4.7. There are numerous
+C++11 problems with 4.6's library, and we don't support GCCs or libstdc++ older
+than 4.7. You will need to update your system and ensure Clang uses the newer
+standard library.
+
+If this error is incorrect or you need to force things to work, you may pass
+'--disable-compiler-version-checks' to configure to bypass this test.])])
+ CXXFLAGS="$llvm_cv_old_cxxflags"
+ fi
+ ;;
+ gcc)
+ AC_MSG_CHECKING([whether GCC is new enough])
+ AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
+#if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 7)
+#error This version of GCC is too old to build LLVM
+#endif
+]])],
+ [AC_MSG_RESULT([yes])],
+ [AC_MSG_RESULT([no])
+ AC_MSG_ERROR([
+The selected GCC C++ compiler is not new enough to build LLVM. Please upgrade
+to GCC 4.7. You may pass --disable-compiler-version-checks to configure to
+bypass these sanity checks.])])
+ ;;
+ unknown)
+ ;;
+ esac
+ AC_LANG_POP([C++])
+ ;;
+ *)
+ AC_MSG_ERROR([Invalid setting for --enable-compiler-version-checks. Use "yes" or "no"])
+ ;;
+esac
+
dnl --enable-cxx11 : check whether or not to use -std=c++11 on the command line
AC_ARG_ENABLE(cxx11,
AS_HELP_STRING([--enable-cxx11],
esac],
llvm_cv_enable_terminfo="yes")
+dnl --enable-libedit: check whether the user wants to turn off libedit.
+AC_ARG_ENABLE(libedit,AS_HELP_STRING(
+ [--enable-libedit],
+ [Use libedit if available (default is YES)]),
+ [case "$enableval" in
+ yes) llvm_cv_enable_libedit="yes" ;;
+ no) llvm_cv_enable_libedit="no" ;;
+ *) AC_MSG_ERROR([Invalid setting for --enable-libedit. Use "yes" or "no"]) ;;
+ esac],
+ llvm_cv_enable_libedit="yes")
+
dnl --enable-libffi : check whether the user wants to turn off libffi:
AC_ARG_ENABLE(libffi,AS_HELP_STRING(
--enable-libffi,[Check for the presence of libffi (default is NO)]),
[Define if the setupterm() function is supported this platform.]))
fi
+dnl The libedit library is optional; used by lib/LineEditor
+if test "$llvm_cv_enable_libedit" = "yes" ; then
+ AC_SEARCH_LIBS(el_init,edit,
+ AC_DEFINE([HAVE_LIBEDIT],[1],
+ [Define if libedit is available on this platform.]))
+fi
+
dnl libffi is optional; used to call external functions from the interpreter
if test "$llvm_cv_enable_libffi" = "yes" ; then
AC_SEARCH_LIBS(ffi_call,ffi,AC_DEFINE([HAVE_FFI_CALL],[1],