Depends-on:
math
-isnanl [test $HAVE_DECL_LDEXPL = 0 || test $gl_func_ldexpl = no]
-fpucw [test $HAVE_DECL_LDEXPL = 0 || test $gl_func_ldexpl = no]
+extensions
+ldexp [{ test $HAVE_DECL_LDEXPL = 0 || test $gl_func_ldexpl = no; } && test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 1]
+isnanl [{ test $HAVE_DECL_LDEXPL = 0 || test $gl_func_ldexpl = no; } && test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 0]
+fpucw [{ test $HAVE_DECL_LDEXPL = 0 || test $gl_func_ldexpl = no; } && test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 0]
configure.ac:
gl_FUNC_LDEXPL