diff options
Diffstat (limited to 'autoconf/configure.ac')
| -rw-r--r-- | autoconf/configure.ac | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/autoconf/configure.ac b/autoconf/configure.ac index 435188e275..89fd237de5 100644 --- a/autoconf/configure.ac +++ b/autoconf/configure.ac @@ -96,6 +96,75 @@ if test "$CXX" = "clang++" ; then AC_LANG_POP([C++]) fi +dnl Set up variables that track whether the host compiler is GCC or Clang where +dnl we can effectively sanity check them. We don't try to sanity check all the +dnl other possible compilers. +AC_MSG_CHECKING([whether GCC or Clang is our host compiler]) +AC_LANG_PUSH([C++]) +llvm_cv_cxx_compiler=unknown +AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#if ! __clang__ + #error + #endif + ]])], + llvm_cv_cxx_compiler=clang, + [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#if ! __GNUC__ + #error + #endif + ]])], + llvm_cv_cxx_compiler=gcc, [])]) +AC_LANG_POP([C++]) +AC_MSG_RESULT([${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. |