G ++似乎无法识别-std = c ++ 11

Question

I compile my code with the flag -std=c++11 given, and I get all kinds of errors depicting that I should use the same flag. Also, auto is not recognised being a type.

Makefile:

GCCPATH = /path/gcc/5.3.0
CC = $(GCCPATH)/bin/g++
DARGS = -ggdb               #debug arguments
CARGS = -std=c++11          #C arguments
WARGS = -Wall -Wextra       #warning arguments
AARGS = $(DARGS) $(CARGS) $(WARGS)  #all arguments
GCCLIBPATH = $(GCCPATH)/lib64
LIBS = -l curl
LIBD = -L $(GCCLIBPATH) -Wl,-rpath=$(GCCLIBPATH)

.PHONY: webspider

webspider: ../title/htmlstreamparser.o filesystem.o
    $(CC) $(AARGS) -o $@ $@.cpp $+ $(LIBS) $(LIBD)

filesystem:
    $(CC) $(AARGS) -c $@.cpp

The warnings and errors I get:

warning: non-static data member initializers only available with -std=c++11 or -std=gnu++11
warning: range-based ‘for’ loops only available with -std=c++11 or -std=gnu++11
error: ‘weblink’ does not name a type
  for(auto weblink: weblinks)

Now my question is: What should I do to make g++ recognise this clearly given flag?
I also tried to replace it with -std=c++0x , to no avail.

EDIT:
Full output of make :

g++    -c -o filesystem.o filesystem.cpp
In file included from filesystem.cpp:1:0:
filesystem.hpp:23:36: warning: non-static data member initializers only available with -std=c++11 or -std=gnu++11
   std::string dir = getCurrentPath();
                                    ^
filesystem.cpp: In member function ‘std::__cxx11::string Filesystem::createMD5(std::__cxx11::string)’:
filesystem.cpp:49:19: warning: range-based ‘for’ loops only available with -std=c++11 or -std=gnu++11
  for(long long c: result)
                   ^
filesystem.cpp: In member function ‘void Filesystem::createLinkIndex(std::__cxx11::string, strVec)’:
filesystem.cpp:57:11: error: ‘weblink’ does not name a type
  for(auto weblink: weblinks) {
           ^
filesystem.cpp:61:1: error: expected ‘;’ before ‘}’ token
 }
 ^
filesystem.cpp:61:1: error: expected primary-expression before ‘}’ token
filesystem.cpp:61:1: error: expected ‘;’ before ‘}’ token
filesystem.cpp:61:1: error: expected primary-expression before ‘}’ token
filesystem.cpp:61:1: error: expected ‘)’ before ‘}’ token
filesystem.cpp:61:1: error: expected primary-expression before ‘}’ token
make: *** [filesystem.o] Error 1

Answer 1

The problem is you do not specify all your dependencies, in particular how to build all your intermediate object files .

So what happens is make makes up its own rules and invisibly sneaks them in while you're not looking.

The way to control these implicit rules is through setting the correct predefined variables :

CXX := $(GCCPATH)/bin/g++      # c++ compiler
CPPFLAGS := -I/path/to/headers # preprocessor flags
CXXFLAGS := -std=c++11         # compiler flags
LDFLAGS := -L/path/to/libs     # linker flags
LDLIBS := -lcurl               # libraries to link
# etc...

By using the correct predefined variables , rather than making up your own, you can save a lot of work when building a Makefile .

Answer 2

In the end, based on the comments, it was fixed by changing

filesystem:
    $(CC) $(AARGS) -c $@.cpp

to

filesystem.o: filesystem.cpp
    $(CC) $(AARGS) -c $+

as Makefile did not understand that I was trying to make filesystem.o with the rule filesystem: ... . When stating this explicitely, it worked as intended.

Advantage of this method over the answer of Galik is the ability to use own variables, albeit in this case not that much of an advantage since it is a small project.