我正在尝试使用make来构建带有子目录的项目,我已经使递归的make部分起作用了,但是由于某种原因,它似乎采用了源文件依赖项的先决条件,并在它们之后附加了.o
,然后尝试编译它们,显然没有用,为什么要这样做?
有问题的规则如下:
operations_cache.o : memory_management/operations_cache.cpp memory_management/operations_cache.hpp \
function.hpp operations/operation_base.hpp
cd memory_management && $(MAKE) $@
编译operations
目录的规则如下:
operation_%.o : function.hpp
cd operations && $(MAKE) $@
出于某种原因,make一直试图说operations/operation_base.hpp.o
是有效的目标,即使我没有在make文件的任何地方列出它。我已经阅读了该文档的文档,但在文档中没有看到任何有关尝试根据必备文件名隐式定义对象的信息,因此,我对使它执行此操作的原因感到非常困惑。
我得到的错误是:
g++ -c -o main.o main.cpp
g++ -c -o node.o node.cpp
cd memory_management && make unique_table.o
make[1]: Entering directory './memory_management'
g++ -o ../unique_table.o -c unique_table.cpp
make[1]: Leaving directory './memory_management'
cd operations && make operations/operation_base.hpp.o
make[1]: Entering directory './operations'
g++ -o ../operations/operation_base.hpp.o -c
g++: fatal error: no input files
compilation terminated.
Makefile:10: recipe for target 'operations/operation_base.hpp.o' failed
make[1]: *** [operations/operation_base.hpp.o] Error 1
make[1]: Leaving directory './operations'
Makefile:24: recipe for target 'operations/operation_base.hpp.o' failed
make: *** [operations/operation_base.hpp.o] Error 2
应用户要求,这是我3个目录的完整文件
./ Makefile
CC = g++
objects = main.o node.o unique_table.o operations_cache.o function.o operation_base.o operation_and.o
# shared_lib = nodelib.so
all : edit # $(shared_lib)
edit : $(objects)
$(CC) -o edit $(objects)
main.o : main.cpp node.hpp memory_management/unique_table.hpp memory_management/operations_cache.hpp
node.o : node.cpp node.hpp
unique_table.o : memory_management/unique_table.cpp memory_management/unique_table.hpp node.hpp
cd memory_management && $(MAKE) $@
operations_cache.o : memory_management/operations_cache.cpp memory_management/operations_cache.hpp \
function.hpp operations/operation_base.hpp
cd memory_management && $(MAKE) $@
function.o : function.cpp function.hpp node.hpp memory_management/unique_table.hpp
operation_%.o : function.hpp
cd operations && $(MAKE) $@
.PHONY : clean
clean :
rm edit $(objects)
./ operations / Makefile
CC = g++
objects = operation_base.o operation_and.o operation_or.o operation_xor.o operation_restrict.o operation_composition.o operation_satisfy.o operation_satisfy_all.o
proj_dir = ../
operation_base.o : operation_base.cpp operation_base.hpp $(proj_dir)function.hpp
operation_and.o : operation_and.cpp operation_and.hpp operation_base.hpp $(proj_dir)function.hpp
operation_or.o : operation_or.cpp operation_or.hpp operation_base.hpp $(proj_dir)function.hpp
operation_xor.o : operation_xor.cpp operation_xor.hpp operation_base.hpp $(proj_dir)function.hpp
operation_composition.o : operation_composition.cpp operation_composition.hpp operation_base.hpp $(proj_dir)function.hpp
operation_restrict.o : operation_restrict.cpp operation_restrict.hpp operation_base.hpp $(proj_dir)function.hpp
operation_satisfy.o : operation_satisfy.cpp operation_satisfy.hpp operation_base.hpp $(proj_dir)function.hpp
operation_satisfy_all.o : operation_satisfy_all.cpp operation_satisfy_all.hpp operation_satisfy.hpp
%.o :
$(CC) -o $(proj_dir)$@ -c $<
./ memory_management / Makefile
CC = g++
objects = operations_cache.o unique_table.o
proj_dir = ../
operations_cache.o : operations_cache.cpp operations_cache.hpp \
$(proj_dir)function.hpp $(proj_dir)operations/operation_base.hpp
unique_table.o : unique_table.cpp unique_table.hpp $(proj_dir)node.hpp
%.o :
$(CC) -o $(proj_dir)$@ -c $<
从memory_management/operations_cache.cpp memory_management/operations_cache.hpp function.hpp operations/operation_base.hpp
行中删除operations_cache.o
解决了这个问题,它不能解释为什么会出现错误,但是可以,但是我仍然想了解为什么会发生这种情况。
这是因为您的operations/operation_base.hpp
恰好与operation_%.o
规则匹配,并且是由于内置规则的事实: