makefile – GNU make 3.81：eval函数不工作？

我最近从GNU make文档中发现了这个引用eval函数的示例代码.我真的很喜欢它,但是当我试图在我的机器上测试(make 3.81 / Debian)时,它所做的只是尝试链接服务器,而不是首先编译c文件？为什么？使3.81不兼容吗？

外壳输出：

$make
cc     -o server
cc: no input files

码：

PROGRAMS    = server client

 server_OBJS = server.o server_priv.o server_access.o
 server_LIBS = priv protocol

 client_OBJS = client.o client_api.o client_mem.o
 client_LIBS = protocol

 # Everything after this is generic

 .PHONY: all
 all: $(PROGRAMS)

 define PROGRAM_template =
  $(1): $$($(1)_OBJS) $$($(1)_LIBS:%=-l%)
  ALL_OBJS   += $$($(1)_OBJS)
 endef

 $(foreach prog,$(PROGRAMS),$(eval $(call PROGRAM_template,$(prog))))

 $(PROGRAMS):
         $(LINK.o) $^ $(LDLIBS) -o $@

 clean:
         rm -f $(ALL_OBJS) $(PROGRAMS)

define PROGRAM_template
  ...
endef