using c++11 with GYP project - c++

Question

I am trying to create a simple cross platform C++ project with gyp. Currently I'm just trying this on a mac - but would like to get it to build for windows, Linux, ios and android eventually.
HEre is the simple gyp file that I'm using.
I would like to be able to use ninja as well as xcode/msvc projects from this gyp.
I know that I need to be able to add
-std=c++11 and -libstdc++ to the commandline for clang, but right now I only see the generated build files using g++ instead of clang.
This is my gyp file.
{
'targets': [
{
'target_name': 'libtest',
'product_name': 'test',
'type': 'static_library',
'sources': [
'./src/lib.cpp',
],
'include_dirs': [
'include',
],
},
{
'target_name': 'testapp',
'type': 'executable',
'sources': [
'./test/test.cpp',
],
'include_dirs': [
'src',
],
'dependencies': [
'libtest'
],
},
],
}

Answer 1

I've sort of figured out this to a certain extent. At lesast I got it working on the mac for a makefile build ( not ninja which was my original hope).
First I had to get gyp to use clang instead of g++ , to do this I had to add a make_global_settings to the gyp file as so. This doesn't seem like a good plan for a crossplatform build. I was also able to set these with environment variables, I'm guessing I can probably do something with conditions to make this specific to the mac.
'make_global_settings': [
['CXX','/usr/bin/clang++'],
['LINK','/usr/bin/clang++'],
],
'targets':
[
......
The other thing I had to do was add an xcode_settings dictionary with OTHER_CPLUSPLUSFLAGS and OTHER_LDFLAGS depending on the target type. Full example below.
{
'make_global_settings': [
['CXX','/usr/bin/clang++'],
['LINK','/usr/bin/clang++'],
],
'targets': [
{
'target_name': 'mylib',
'product_name': 'mylib',
'type': 'static_library',
'sources': [
'src/implementation.cc',
],
'include_dirs': [
'include',
],
'conditions': [
[ 'OS=="mac"', {
'xcode_settings': {
'OTHER_CPLUSPLUSFLAGS' : ['-stdlib=libc++'],
},
}],
],
},
{
'target_name': 'myapp',
'type': 'executable',
'sources': [
'./bin/myapp.cc',
],
'conditions': [
[ 'OS=="mac"', {
'xcode_settings': {
'OTHER_CPLUSPLUSFLAGS' : ['-std=c++11','-stdlib=libc++'],
'OTHER_LDFLAGS': ['-stdlib=libc++'],
},
}],
],
'include_dirs': [
'include',
],
'dependencies': [
'mylib'
],
},
],
}

Answer 2

So I just tried this on the clang++ 6 OSX 10.10 and I ran into the same problem that drewish hit.
Adding -mmacosx-version-min=10.7 to the OTHER_CPLUSPLUSFLAGS and OTHER_LDFLAGS arrays fixed the issue.
EDIT
An even better way that I found to fix this is to add "MACOSX_DEPLOYMENT_TARGET": "10.7" into the xcode_settings array. This will override any defaults that Node sets in its common.gypi file.
So it should look something like this
{
'targets': [
{
'target_name': 'myApp',
'sources': [ 'myApp.cc' ]
'conditions': [
['OS=="mac"', {
'xcode_settings': {
'MACOSX_DEPLOYMENT_TARGET': '10.7'
}
}]
]
}
]
}

Answer 3

johnhaley81's solution is really the simplest one to get this working (at least on OSX), however I had to add a few more settings:
"conditions": [
[ 'OS=="mac"', {
"xcode_settings": {
'MACOSX_DEPLOYMENT_TARGET': '10.9',
"CLANG_CXX_LIBRARY": "libc++",
"GCC_ENABLE_CPP_RTTI": "YES",
"GCC_ENABLE_CPP_EXCEPTIONS": "YES"
},
}],
],
As you can see, you can directly use the name/value pairs from an XCode project here. Pretty handy.

Answer 4

The previous answers were helpful, but all that must actually be added to xcode_settings are 'MACOSX_DEPLOYMENT_TARGET': '10.7' and 'CLANG_CXX_LIBRARY': 'libc++'
{
'targets': [
{
'target_name': 'myApp',
'sources': [ 'myApp.cc' ]
'conditions': [
['OS=="mac"', {
'xcode_settings': {
'MACOSX_DEPLOYMENT_TARGET': '10.7',
'CLANG_CXX_LIBRARY': 'libc++'
}
}]
]
}
]
}
Specifically, the option 'CLANG_CXX_LIBRARY': 'libc++' is what's getting us what we want. If you add this option without 'MACOSX_DEPLOYMENT_TARGET': '10.7' then you might see the following error:
clang: error: invalid deployment target for -stdlib=libc++ (requires OS X 10.7 or later)
This error indicates that 10.7 is a more appropriate value than 10.9 for MACOSX_DEPLOYMENT_TARGET if you're interested in compatibility.