about clang++ requirements for C++11 - c++11

I would like to build some code in new C++11. Our machine allows only g++4.4.7 that is old for that. We have available also clang++ 3.4 that as far as I understood supports the new features.
While I am doing first tests with clang++ it looks like it does requires c++ header files from g++. Having available version g++4.4 this will prevent my code to use the new C++11.
Is it really so? Is there a way where I can use clang++3.4 to build C++11 code without having latest versions of g++ ?

Try libc++, on linux should work just fine
http://libcxx.llvm.org/

Related

AVX and newer intrinsics with GCC on Mac; what assembler would one need?

I have been tweaking GCC 6.3.0 to get it to use the libc++ runtime instead of libstdc++ so that g++ can be used without worrying about C++ runtime incompatibilities:
https://github.com/RJVB/macstrop/tree/master/lang/gcc6
The tweak works, I can build and run KDE software using g++ against Qt5 and KF5 frameworks (and everything else) built with various clang versions.
What doesn't work is generating code that uses AVX and presumably most or all newer intrinsic instructions.
This is not a new issue that's never been invoked on here; it's answered here for instance: How to use AVX/pclmulqdq on Mac OS X
Evidently one can configure gcc to call the linked script instead of the actual as executable.
But can gcc not be configured to use another assembler altogether, like nasm, and would that solve this issue?

g++ (tdm-1) 4.7.1 doesnt support all c++11 features

it's supposed g++ (tdm-1) 4.7.1 that comes with codeblocks for windows support all C++11 features, std::stoi(str) isnt reconized, same for other c++11 functions. (string header is included).
Do i need to look for another compiler ?
This is due to missing C library functions in MinGW, see the last few comments on https://gcc.gnu.org/bugzilla/show_bug.cgi?id=37522
I made some improvements so it is supported in MinGW GCC 4.9 and later, so you could just upgrade to a later TDM build.

Proper way to upgrade from llvm-g++-4.2 to g++-4.7 on Mac

I have Lion 10.7.3 with the Command-line tool installed. I wanted to experiment with C++11, so I used homebrew to install GCC 4.7 as documented here.
How can I now upgrade the /usr/bin/g++ to be the one installed by Homebrew? Is it as simple as symlinking it? I just want to double check and make sure. Thanks!
First, are you sure you need g++ 4.7? As you can see from the C++11 implementation status page, recent versions of clang support most of C++11 too. Of course there are still things that g++ handles and clang doesn't, but there are also still things that clang supports and g++ doesn't. And, more importantly, you already have a recent version of clang, from Apple, configured and ready to go, as your default compiler. Plus, g++ after 4.2 doesn't support Mac extensions like, say, -arch, which means you can't use it to build a whole lot of third-party software (because most configure scripts assume that if you're on a Mac, your compiler supports Mac extensions).
But if you want g++ 4.7, you can do it. Just not by trying to replace /usr/bin/g++ with a different version. Never replace anything in /usr/bin (or /System) with non-Apple stuff except in a few very rare cases (when you have a strong reassurance from someone who knows what they're talking about).
A better thing to do is to just install another compiler in parallel. Just let Homebrew install its favorite way (so it installs into some prefix like /usr/local/Cellar/gcc/4.7, then symlinks all the appropriate stuff into /usr/local/bin, etc.), and use it that way.
When compiling your code, instead of writing g++, write /usr/local/bin/g++, or g++-4.7.
If you get tired of doing that, put /usr/local/bin higher on your PATH that /usr/bin, or create a shell alias, or stick it in the environment variable CXX and write $CXX instead of g++.
If you're using a GUI IDE, you should be able to configure it to use your compiler by setting the path to it somewhere. (Unless you're using Xcode, which you can only configure to work with Apple-tested compilers.)
This is all you need for experimenting with your own code. If you want to compile third-party applications with this compiler, that may be a bit more complicated. You don't often actually compile each source file and link the result together; you just do configure && make and let them do the heavy lifting for you.
Fortunately, most packages will respect the standard environment variables, especially CXX for specifying a default C++ compiler and CC for a default C compiler. (That's why I suggested the name CXX above.)
Just remember that, again, g++ 4.7 doesn't support Mac extensions, so if you're not prepared to debug a bunch of autoconf-based configure scripts complaining that your compiler can't generate code because it assumed it could throw -arch x86_64 at any compiler on a Mac, etc., don't do this.

Using non-apple g++ on Mac OSX Lion

Is it possible to use the stock (non-apple) version of g++ on Mac OSX 10.7? I want to be able to use the stock g++ without running a virtual linux box on my mac. The reason I want to do this is because apple's version of g++ doesn't warn you when there are unused variables and etc. I'm doing some assessed C++ problems in my numerical methods course and I want to make sure I'm not making any mistakes.
It was suggested I make a symbolic link to a linux version of g++ for compiling the code for the assessments. How do I go about doing that?
Thanks
A linux version of the compiler will not work on what is (essentially) a bsd port.
Are you sure that the current version of g++ cannot warn on the conditions you expect?
Finally, if #2 is true, there is nothing stopping you from getting another version of g++ (compiled for MacOSX) that doesn't have this issue.
A binary for g++ for Linux won't run on MacOSX.
You could compile GCC from its source code; use the latest release i.e. 4.6.2. But that requires some work. Be sure to follow the installation instructions, in particular care about dependencies (like PPL & Cloog) and configure (appropriately) and compile in a build tree outside of the source tree.

Cross compiling gcc

Im trying to get gcc running on my Kindle 3. I have a native terminal and ssh working, and I found that the Sourcery G++ toolchain for arm eabi linux produces working binaries, so it seems like I should be able to just configure gcc to build using arm-none-eabi-gcc and compile it, but Im obviously misunderstanding something... When I configure with --target=arm-none-eabi --host=arm-none-eabi and run make, it compiles using gcc, not arm-none-eabi-gcc. Unless theres some pre-compilation phase that uses gcc? I havent gotten all the way through the build yet, since Ive had other errors im working through, but I dont want to waste all this time if im configuring something wrong in the beginning. I found this question, Compile GCC with Code Sourcery where the op seems to want the same thing, but it was never answered... Also, Ive run into problems when compiling lua with the sourcery compiler, it seems to be using a different version of GLIBC, which I assume will be a problem. Is there any easier way to do this?
/pathToStuffifNotPathed/arm-none-linux-gnueabi-g++ foo.c
Should you not invoke the compiler via it's tool-chain invocation? I believe so.

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