| # We just try to figure out where hash<> is defined. It's in some file |
| # that ends in hash_fun.h... |
| # |
| # Ideally we'd use AC_CACHE_CHECK, but that only lets us store one value |
| # at a time, and we need to store two (filename and namespace). |
| # prints messages itself, so we have to do the message-printing ourselves |
| # via AC_MSG_CHECKING + AC_MSG_RESULT. (TODO(csilvers): can we cache?) |
| # |
| # tr1/functional_hash.h: new gcc's with tr1 support |
| # stl_hash_fun.h: old gcc's (gc2.95?) |
| # ext/hash_fun.h: newer gcc's (gcc4) |
| # stl/_hash_fun.h: STLport |
| |
| AC_DEFUN([AC_CXX_STL_HASH_FUN], |
| [AC_REQUIRE([AC_CXX_STL_HASH]) |
| AC_MSG_CHECKING(how to include hash_fun directly) |
| AC_LANG_SAVE |
| AC_LANG_CPLUSPLUS |
| ac_cv_cxx_stl_hash_fun="" |
| for location in functional tr1/functional \ |
| ext/hash_fun.h ext/stl_hash_fun.h \ |
| hash_fun.h stl_hash_fun.h \ |
| stl/_hash_fun.h; do |
| if test -z "$ac_cv_cxx_stl_hash_fun"; then |
| AC_TRY_COMPILE([#include <$location>], |
| [int x = ${ac_cv_cxx_hash_namespace}::hash<int>()(5)], |
| [ac_cv_cxx_stl_hash_fun="<$location>";]) |
| fi |
| done |
| AC_LANG_RESTORE |
| AC_DEFINE_UNQUOTED(HASH_FUN_H,$ac_cv_cxx_stl_hash_fun, |
| [the location of the header defining hash functions]) |
| AC_DEFINE_UNQUOTED(HASH_NAMESPACE,$ac_cv_cxx_hash_namespace, |
| [the namespace of the hash<> function]) |
| AC_MSG_RESULT([$ac_cv_cxx_stl_hash_fun]) |
| ]) |
