-AC_CHECK_FUNCS([GC_do_blocking GC_call_with_gc_active GC_pthread_exit GC_pthread_cancel GC_allow_register_threads GC_pthread_sigmask GC_set_start_callback GC_get_suspend_signal GC_move_disappearing_link GC_get_heap_usage_safe GC_get_free_space_divisor GC_gcollect_and_unmap GC_get_unmapped_bytes])
-
-# Though the `GC_do_blocking ()' symbol is present in GC 7.1, it is not
-# declared, and has a different type (returning void instead of
-# void*).
-AC_CHECK_DECL([GC_do_blocking],
- [AC_DEFINE([HAVE_DECL_GC_DO_BLOCKING], [1],
- [Define this if the `GC_do_blocking ()' function is declared])],
- [],
- [#include <gc/gc.h>])
-
-# `GC_fn_type' is not available in GC 7.1 and earlier.
-AC_CHECK_TYPE([GC_fn_type],
- [AC_DEFINE([HAVE_GC_FN_TYPE], [1],
- [Define this if the `GC_fn_type' type is available.])],
- [],
- [#include <gc/gc.h>])
+# Functions that might not be defined, depending on configuration.
+AC_CHECK_FUNCS([GC_pthread_exit GC_pthread_cancel GC_pthread_sigmask])