I have to install a package (spatial-correlation-sampler) which calls for gcc: >=5.3. On my system (Linux, remote server), gcc version is 4.8.5, and a Conda virtual environment uses the same version. Is it possible to use a different version within the virtual environment?
Is it possible to use a different gcc version inside a Conda environment?
Probably yes, except if you (or your Conda environment) needs or uses some GCC plugin. These plugins are specific to a particular version of GCC: a plugin coded for GCC 4.8 (such as my old GCC MELT) won't work with GCC 6. But see also this draft report on Bismon (which might become a successor to GCC MELT).
On Linux/x86-64, a C code compiled with GCC 4.8 would be compatible with the same code compiled with GCC 10, since both follow the same ABI and calling conventions.
For C++ code compiled with GCC, there could be subtle ABI or calling conventions incompatibilities (related to name mangling and exceptions).
Be also aware that Python 2 and Python 3 have different foreign function interfaces. Read chapters related to extending and embedding the Python interpreter.
See also the Program Library HowTo, Advanced Linux Programming and C++ dlopen mini-HowTo and Linux Assembly HowTo and of course Linux From Scratch.
On my system (Linux, remote server), gcc version is 4.8.5
GCC is Free Software.
You are allowed to compile and install a more recent GCC from its source code on your system. An installed GCC 4.8 can be use to build e.g. a GCC 8 from its source code (then installed into /usr/local/bin/gcc, then you just configure wisely your $PATH variable). You could even do that with the unsupported GCC 5.
On recent Debian or Ubuntu you would install dependencies with something like sudo aptitude build-dep g++ and you might also want to use Docker. You may need to download several gigabytes.
Some companies or freelancers are able (for a fee) to compile a GCC tailored for your system. I know AdaCore, but there are many others corporations or freelancers selling support on GCC. Contact me by email for more.
PS. On a powerful AMD Threadripper 2970WX desktop, I just built GCC 10.1 with make -j8 and g++ 9.3 on Debian/Sid in 10:21.38 elapsed time, requiring less than 7 Gbytes of disk space (for both GCC source code and object files). Of course, I disabled the compiler bootstrap. You could do the same thru ssh to your system (it could take an hour or two of elapsed time, because a Linux VPS has less cores so you might need to just make -j2).
Related
I'm looking for a cross compiler to compile for linux under the msys2 environment.
I'm looking for somethink like x86_64-w64-linux-gcc. But I can't find it.
Which package I have to install?
You'll need a VM or a Linux machine to test the resulting binaries, so I'd just compile on one in the first place.
But cross-compilation should be possible too:
Boot up your favorite Linux distribution in a VM.
Install the libraries you want to have. Install g++ to get libstdc++, and possibly other basic libraries.
Copy the root directory / from the VM to the Windows machine.
You only need headers and libraries, not everything. You'll have to experiment to know what directories can or can't be safely removed.
Install Clang on the Windows machine. Installing LLD is also a good idea (it's a separate package in MSYS2; or, if you're using the official Clang binaries, it's bundled with them).
We're using Clang, because it's inherently a cross-compiler, i.e. doesn't require separate binaries to target a different platform, unlike GCC.
Compile with Clang with --target=x86_64-pc-linux-gnu --sysroot=path/to/root/directory.
-fuse-ld=lld is probably a good idea as well.
The string x86_64-pc-linux-gnu was obtained by running clang++ --version on a Linux machine.
You might need a few more flags, but this should be a good starting point.
My developing/producing environments are all CentOS-7.7.
In order to compile my program with gcc-8.3.0, I have installed "devtoolset-8" on my developing env, but it can not be used in the way same as gcc-4.8.5 that was shipped with CentOS7 oringinally.
Every time I need to compile a program, I must use "scl enable devtoolset-8 -- bash" to switch to gcc8 instead of gcc4.8.5.
When the program was deploying onto the producing-env, there is no gcc8, nor libstdc++.so.6.0.25, so it can not run.
I guess libstdc++.so.6.0.25 should be released with gcc8? I can neither install "devtoolset-8" on the producing-env, nor build gcc8 from source on the producing env.
The version of libstdc++ that can be installed from the official yum repo of CentOS, is libstdc++.so.6.0.19, hence my programs can not be loaded at the producing-env.
How to let such programs to run?
Thanks!
Pls forgive my Ugly English.
In order to not have to copy or ship a separate libstdc++.so but rather link statically (as suggested in a comment) against the C++ runtime, one can link C++ programs with -static-libstdc++ (also specifying -static-libgcc will also make sure that the program does not depend on a recent enough version of libgcc_s.so on the system - although that should rarely be a problem).
There can also be the issue of the target system having a version of glibc that is too old (relative to the build system). In that case, one could anyhow compile gcc of no matter how recent of a version on the older system, so that the resulting C++ executables as well as libstdc++ are linked against the older glibc. Linking C++ programs with -static-libstdc++ will again help to not depend on the program having to be able to find libstdc++.so at run-time.
Finally, the C++ program could also be linked with -static not depending on any dynamic libraries at all.
First Question: What is the best way to support various 'standard' Linux platforms with a single C++11 binary?
This binary uses a handful of third party libraries including boost, zlib, xml2, openssl (all of which
I can build statically).
The binary must run on a variety of Linux platforms for x86_64: Ubuntu 16.04 and 14.04, Centos 7.2 and Debian.
Soon it must run on Darwin x86_64 and Ubuntu 16.04 on a Beagle Bone Black.
The default versions of compilers, libstdc++ and libc runtimes vary quite a bit on these platforms.
I have had some Linux success building on Ubuntu 14.04 with an upgraded (toolchain r-test) g++ 5.3 compiler
using these compiler options (note not using the "-static" switch):
-static-libstdc++ -static-libgcc -D_GLIBCXX_USE_CXX11_ABI=0
However, this requires installing the upgraded 5.3 compiler on the host (default is 4.9 IIRC) and
some runtime libs on the target platforms which is not preferred and risks issues with libc.so.
If it should be determined that this sort of solution is best, then I would prefer to build on
16.04 with the newest g++ or clang with switches so the binary runs on older platforms with
minimal changes to defaults. Yes, I know I am perhaps asking for the moon :)
Second question: instead of one binary, maybe one compiler and libc for all platforms including Darwin and Windows?
I was also considering an attempt to use musl to create a 'more consistently behaved binary. I could consider using clang instead of g++.
Anyone with experience/recommendations? I would very much like to avoid maintaining
separate compilations and combinations of third-party libs and compilers and settings and upgrades for each platform (especially for Linux targets but pretty typical for different operating systems).
Using the same version of the same compiler and possibly the same version of a libc would be best
but may not be possible: clang with musl?
Thanks
According to the address-sanitizer home page it comes only with the gcc 4.8 or above. Isn't there anyway of using it with gcc 4.7?
No, there is no reliable way (to get ASAN before GCC 4.8). ASAN requires compiler support and is very intimately connected to your particular compiler (and version, and host and target systems, and specific configuration, etc...)
In other words, try to compile a recent GCC (that is, GCC 5.2 in july 2015; use that since ASAN did progress since 4.8 and you'll get more -fsanitize= options in recent versions of GCC) from its downloaded source code. See hints here & there. You should try some recent Linux distribution.
(on Linux or other POSIX systems, you don't need root privileges to configure, compile, and install gcc-mine-5 in $HOME/soft/; you need appropriate ../gcc-5.2/configure options, notably --prefix=$HOME/soft --program-suffix=-mine-5, then add $HOME/soft/bin/ in your PATH then run with CC=gcc-mine-5 e.g. for make)
I have started working on linux for about 6 months or so and now I
wanted to compile Linux version 2.6.39. Here are my questions for
the upgrade :
a. How will I get the GCC, Make, BinUtil and other tool dependency
of linux with their versions.
b. After compiling the tools how to make toolchain for linux
compilation.
I have searched various websites for this. I got information in bits and pieces and for specific linux versions. Is their a site or something where I can get all the information about the upcoming linux upgrades with the details.
My Current Linux machine details are :
Distro : CentOS 4.8
Linux version : 2.6.9
Gcc Version : 3.4.6
Binutils : 2.15.92
Make : 3.80
-Tommy
There are 2 options, depending on that type of kernel you want to build:
If you want a kernel for your machine (or a similar one), you can use the GCC that you already have from your distro.
If you want a kernel for another architecture (like ARM, MIPS, etc) you NEED a cross-compiler. You can build a cross-compiler (a whole toolchain, actually) using something like crosstool-ng.
With crosstool-ng you can also build yourself a toolchain for the first case. This tool take care of downloading the tarballs with the sources for GCC, Binutils, glibc, etc.
If you just want to upgrade the kernel on your machine, regardless of the version, the steps are mostly the same:
Get the source with
wget https://www.kernel.org/pub/linux/kernel/v3.0/linux-3.2.9.tar.bz2 or something similar
extract them with tar xjvf linux-*.tar.bz2 and then exter that folder
make oldconfig or make menuconfig or even better make localmodconfig
make
make install as root