The AC_CHECK_HEADER
macro is using the C
compiler by default. You can change the current language using: AC_LANG([C++])
or: AC_LANG_PUSH([C++]) / AC_LANG_POP
- as described in the (single-page) manual. e.g.,
...
AC_LANG([C++])
AC_CHECK_HEADERS([google/sparse_hash_map])
# still in C++ 'mode'
or:
...
AC_LANG_PUSH([C++])
AC_CHECK_HEADERS([google/sparse_hash_map])
AC_LANG_POP([C++])
# restored previous language 'mode'