How do I enable C++11 in gcc?

Guddu picture Guddu · Jun 2, 2013 · Viewed 289.6k times · Source

I use gcc 4.8.1 from http://hpc.sourceforge.net on Mac OSX Mountain Lion. I am trying to compile a C++ program which uses the to_string function in <string>. I need to use the flag -std=c++11 every time:

g++ -std=c++11 -o testcode1 code1.cpp

Is there a way to include this flag by default?

Answer

Silouane Gerin picture Silouane Gerin · Jun 2, 2013

H2CO3 is right, you can use a makefile with the CXXFLAGS set with -std=c++11 A makefile is a simple text file with instructions about how to compile your program. Create a new file named Makefile (with a capital M). To automatically compile your code just type the make command in a terminal. You may have to install make.

Here's a simple one :

CXX=clang++
CXXFLAGS=-g -std=c++11 -Wall -pedantic
BIN=prog

SRC=$(wildcard *.cpp)
OBJ=$(SRC:%.cpp=%.o)

all: $(OBJ)
    $(CXX) -o $(BIN) $^

%.o: %.c
    $(CXX) $@ -c $<

clean:
    rm -f *.o
    rm $(BIN)

It assumes that all the .cpp files are in the same directory as the makefile. But you can easily tweak your makefile to support a src, include and build directories.

Edit : I modified the default c++ compiler, my version of g++ isn't up-to-date. With clang++ this makefile works fine.