I work on CentOS 5.5 and my computer used gcc-4.1.2 until now, and under /usr/lib/gcc/x86_64-redhat-linux/ there were 2 indexes: 4.1.1 and 4.1.2. For using some softwares I must update the gcc.
But after I installed gcc-4.7.0 from the downloaded gcc-4.7.0.tar.gz (I did not use yum because when I tried it all servers told me that I had the latest version which was certainly not true, and perhaps this was also caused by the problem I now face with), the /usr/lib/gcc/x86_64-redhat-linux/4.7.0/ was created just like the 4.1.1 and 4.1.2 index, so under /usr/lib/gcc/x86_64-redhat-linux/ there were 3 indexes: 4.1.1, 4.1.2 and 4.7.0. And under /usr/lib/gcc/x86_64-redhat-linux/4.7.0/ there were 6 indexes:
bin include lib lib64 libexex share
It looked like that 4.7.0 was successfully installed but when I ran
gcc --version
the result was still
gcc (GCC) 4.1.2 20080704 (Red Hat 4.1.2-48)
Copyright (C) 2006 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is
NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
I also ran
update-alternatives --install /usr/bin/gcc gcc /usr/lib/gcc/x86_64-redhat-linux/4.7.0 40
to raise the priority of 4.7.0, and when I ran
update-alternatives --config gcc
it said
There is 1 program that provides 'gcc'.
Selection Command
-----------------------------------------------
*+ 1 /usr/lib/gcc/x86_64-redhat-linux/4.7.0
Enter to keep the current selection[+], or type selection number:
And I printed 1, all it looked like that 4.7.0 was selected as the default gcc, but when I ran gcc --version, the result was not changed! Still 4.1.2.
After that I even removed all 4.1.2 gcc and its related programs by rpm -e and deleted the index, but the result of gcc --version became
-bash: gcc: command not found.
It didn’t change when I reinstalled the 4.7.0.
After all, when I looked for the links of /usr/bin/gcc/ I found
/usr/bin/gcc -> /etc/alternatives/gcc
and link of /etc/alternatives/gcc was
/etc/alternatives/gcc -> /usr/lib/gcc/x86_64-redhat-linux/4.7.0
this should be the result of my running the update-alternatives line, so it has worked. It did make the link to 4.7.0. So why didn’t this link call 4.7.0 in the end? I can’t find out.
I even made the direct link to 4.7.0 then:
ln -s /usr/lib/gcc/x86_64-redhat-linux/4.7.0 /usr/bin/gcc
however this still didn’t work.
I am very confused with it. I will be grateful for your help. Thank you very much!
p.s. Thank Basile Starynkevitch very much for noticing me to make these explanations:
I have /usr/bin/ in my PATH, so this should be OK.
I am teached that /usr/bin/gcc/ should be linked to an executable but not index, so the link to 4.7.0 is wrong. But could anyone tell me which executable to link to, or which executable is /usr/bin/ linked to in a common computer? This may very likely lead to the solution to the problem.
I cannot run configure one more time because configure itself requires gcc but now it is not found. So I'm afraid the problem cannot be fixed by that.
Be aware of the PATH variable. You could have some $HOME/bin/ in it.
Restore your system's gcc (so undo all the mess you have done). Then run which gcc and gcc -v to understand what is it exactly.
If you compile GCC from its source code (as distributed by the FSF), choose a recent version, e.g. GCC 8 in fall 2018.
Read carefully about installing GCC. Compile it outside of its source code. Be aware of the many configure options. I suggest to consider configuring it with some --program-suffix option (such as --program-suffix=-8) and then adding symlinks (e.g. $HOME/bin/gcc -> /usr/local/bin/gcc-8) appropriately.
ln -s /usr/lib/gcc/x86_64-redhat-linux/4.7.0 /usr/bin/gcc
it is wrong. Since /usr/lib/gcc/x86_64-redhat-linux/4.7.0/ is some internal directory, and /usr/bin/gcc has to be an executable.
You probably don't need to run update-alternatives, but you do need to add (cleverly) something in a directory mentioned in your PATH
See also this answer to a similar question.
after edits in the question
You need first to clean up the mess you did under /usr/ (in particular in /usr/bin/ which you should never change without your package system). Remove all the things you added under /usr/bin/ and /usr/lib/. Then re-install forcibly and explicitly appropriate system gcc packages (using yum or some other package manager).
I have /usr/bin/ in my PATH, so this should be OK.
Probably not. My recommendation is to have $HOME/bin/ and /usr/local/bin/ early in your PATH (so before /usr/bin/; you might need to edit ~/.bashrc to change your PATH setting) and to add your new gcc, as something like gcc-8 (if you compile GCC 8 from its source code), there. If you want a system wide installation, have some /usr/local/bin/gcc-8 program. If you want a personal installation, have some $HOME/bin/gcc-8 program (both could be absolute symlinks to somewhere else).
Related
I've recently started working on a project that requires my complier to be above GNAT 4.8.5 - When I go to: Help > About
You can see that the version I'm using is 4.8.5
Also, when I run the gnatls -v command, I can see this...
[parallels#localhost ~]$ gnatls -v
GNATLS 4.8.5 20150623 (Red Hat 4.8.5-39)
Copyright (C) 1997-2013, Free Software Foundation, Inc.
Source Search Path:
<Current_Directory>
/usr/lib/gcc/x86_64-redhat-linux/4.8.5/adainclude/
Object Search Path:
<Current_Directory>
/usr/lib/gcc/x86_64-redhat-linux/4.8.5/adalib/
Project Search Path:
<Current_Directory>
/usr/x86_64-redhat-linux/lib/gnat
/usr/share/gpr
/usr/lib/gnat
[parallels#localhost ~]$ gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/local/libexec/gcc/x86_64-pc-linux-gnu/7.3.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ./configure --disable-multilib --enable-languages=c,c++,ada
Thread model: posix
gcc version 7.3.0 (GCC)
[parallels#localhost ~]$
Please could someone be able to tell me how to update my GNAT compiler? Also, I'm using the Centos 7 Operating System.
Thank you,
Lloyd
You don't need to install a compiler, you already have 3 (at least):
gcc 4.8.5 (the system compiler) in /usr/bin
gcc 7.3.0 (that you just built) in /usr/local/bin
gcc 8.3.1 (from GNAT CE 2019) in /home/parallels/opt/GNAT/2019/bin
Your PATH determines which GCC you pick up when you say just gcc, and which GNATLS you pick up when you say just gnatls, .. etc.
According to a previous post, your PATH is:
$ echo $PATH
/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/bin:/sbin:/var/lib/snapd/snap/bin:/home/parallels/.local/bin:/home/parallels/bin/home/parallels/opt/GNAT/2019/bin/home/parallels/opt/GNAT/2019/bin
so when you say just gcc the system looks at the first entry in the PATH (which is colon-separated) and .. there it is! so it executes that.
If you'd built your 7.3.0 GCC with Ada support, it would have found gnatls in the same place. I have a very strong suspicion that you didn't, so when you say just gnatls the system looks in /usr/local/bin - no luck - then in /usr/local/sbin - no luck - then in /usr/bin - whoopee! but that's the 4.8.5 GCC that you don't want.
Looking again at your PATH, the last part is mangled - you've added /home/parallels/bin and /home/parallels/opt/GNAT/2019/bin (twice) without including the colon separators, resulting in a nonexistent path. (/home/parallels/bin may well have been added by the system - I assume that /home/parallels is your home directory).
What you need to do is to make sure that you pick up the compiler that came with GNAT CE 2019 by putting its location first in your PATH. One way of doing this is by editing your shell startup files.
I don't know how CENTOS sets accounts up, and I don't know what your shell is. Assuming it's bash (type ps -p $$, should come back with bash or perhaps -bash; anything else, I can't help), you need to edit one of the shell startup files - I'm a little unclear about this, but I think it'll be ~/.bashrc (~ is shorthand for your home directory); see here for the gory details. Find the last mention of PATH and immediately after that line insert
export PATH=/home/parallels/opt/GNAT/2019/bin:$PATH
Open a new terminal window and say e.g. gnatls -v - you should pick up the GNAT CE 2019 one.
Only way I know of updating GNAT GPS CE from AdaCore is downloading the new one, installing it and then deleting the old one.
Another thing is to upgrade the gnat-gps that some systems had in ther repositories
I have installed clang 3.8 from the base repositories for both Debian Jessie and Fedora 24. When I try to compile a simple HelloWorld.cpp test program with clang++, and i pass the -fopenmp flag, in both cases i get the same error:
/usr/bin/ld: cannot find -lomp
clang-3.8: error: linker command failed with exit code 1 (use -v to see invocation)
I see that if I instead pass -fopenmp=libgomp, it works. However, the Clang OpenMP website says that the OpenMP runtime is shipped with Clang 3.8. Why, then, can it not find the default libomp library? I do not see this library anywhere on my system.
There is good chances that the OpenMP development package is missing on your system.
On Ubuntu: sudo apt install libomp-dev
If you have libomp installed correctly you will need to use -fopenmp=libomp. libgomp is for gcc. You might check that clang isn't symbollically linked to gcc on your computer.
TL;DR
If you have libomp.so for llvm in somewhere like /usr/lib/llvm-12/lib make file /etc/ld.so.conf.d/libomp.conf with the line /usr/lib/llvm-12/lib in it, then run sudo ldconfig.
Intro
In my case, I had libomp-12-dev installed, but it was not in my linker's library path. See the footnote on how I found the library. There are a couple solutions in this scenario:
Add library path with ldconfig
If you want this in your default library path, consider using ldconfig [man page].
This will look for files in /etc/ld.so.conf. For me, running Ubuntu 20.04, this file only points to including files in the directory /etc/ld.so.conf.d.
$ cat /etc/ld.so.conf
include /etc/ld.so.conf.d/*.conf
As such, I made a config llvm-libomp-12 in my /etc/ld.so.conf.d directory that looks like this:
$ cat /etc/ld.so.conf.d/libomp.conf
# libomp.so for llvm
/usr/lib/llvm-12/lib
Then I asked ldconfig to update the paths with sudo ldconfig. You can add the -v flag and it will print all libraries and paths it is aware of.
Add library to environment variable
We can also direct the linker to our library using the $LD_LIBRARY_PATH environment variable
This may be advantageous if you're on a multiuser system and don't want to impact others, or if you have temporary changes to your library paths you would like to make in your shell.
See what your current $LD_LIBRARY_PATH is with echo $LD_LIBRARY_PATH. You may not have this set by default. Add paths to this variable, each delimited by a colon.
For your current shell session, simply append or prepend to your $LD_LIBRARY_PATH like this (assuming bash, zsh, or fish >v3.0):
export "$LD_LIBRARY_PATH:/path/to/lib"
Or for a more permanent change limited to your user, add the above export to your shell's config file (e.g. ~/.bashrc).
Manually specify library path(s) in compiler flags
Nice for a one-off specific library that you don't always want in your default library paths. Specify the path to the library as a flag like this:
-L/path/to/lib
For example:
clang++ -L/usr/lib/llvm-12/lib [...]
make -L/usr/lib/llvm-12/lib
Footnotes
On searching
If you don't know where a given library you need is, you can use things like find. Personally though, I used a package called mlocate that indexes files on my machine and allows you to search them.
Installing mlocate
sudo apt install mlocate
Updating the indexes
sudo updatedb
Searching for a substring
locate libomp.so
When I searched for where my libomp libraries were, I did this:
$ locate libomp.so
/usr/lib/llvm-12/lib/libomp.so
/usr/lib/llvm-12/lib/libomp.so.5
/usr/lib/x86_64-linux-gnu/libomp.so.5
Notably it seemed like clang was using the libomp.so.5 in the linux-gnu directory, but I needed it to be using the llvm library.
Environment used in this post
$ lsb_release --all
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 20.04.2 LTS
Release: 20.04
Codename: focal
$ uname -a
Linux bip 5.8.0-48-generic #54~20.04.1-Ubuntu SMP Sat Mar 20 13:40:25 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
TODO
Some notes that could be added to this question:
Confirm and list priority of env vars vs config files vs flags (does this vary between compilers and linkers?)
Ordering library paths when using multiple config files (can we prefix with numbers to ensure the order libraries are parsed?)
I am new to Cuda, and I am trying to compile this simple test_1.cu file:
#include <stdio.h>
__global__ void kernel(void)
{
}
int main (void)
{
kernel<<<1,1>>>();
printf( "Hello, World!\n");
return 0;
}
using this: nvcc test_1.cu
The output I get is:
In file included from /usr/local/cuda/bin/../include/cuda_runtime.h:59:0,
from <command-line>:0:
/usr/local/cuda/bin/../include/host_config.h:82:2: error: #error -- unsupported GNU version! gcc 4.5 and up are not supported!
my gcc --version:
gcc (Ubuntu/Linaro 4.6.1-9ubuntu3) 4.6.1
Copyright (C) 2011 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
How can I install a second version of gcc (4.4 -) along with 4.6 without messing everything up?
I found this old topic:
CUDA incompatible with my gcc version
the answer was:
gcc 4.5 and 4.6 are not supported with CUDA - code won't compile and
the rest of the toolchain, including cuda-gdb, won't work properly.
You cannot use them, and the restriction is non-negotiable.
Your only solution is to install a gcc 4.4 version as a second
compiler (most distributions will allow that). There is an option to
nvcc --compiler-bindir which can be used to point to an alternative
compiler. Create a local directory and the make symbolic links to the
supported gcc version executables. Pass that local directory to nvcc
via the --compiler-bindir option, and you should be able to compile
CUDA code without effecting the rest of your system.
But I have no idea how to do it
In my case I didn't have root rights, so I couldn't fully replace the current gcc (4.7) with the older version 4.4 (which I think would be a bad alternative). Although I did have rights where CUDA was installed. My solution was to create an extra folder (e.g. /somepath/gccfornvcc/), wherever I had rights, then to create a link to an nvcc accepted compiler. I already had gcc 4.4 available (but you can install it, without removing your current version).
ln -s [path to gcc 4.4]/gcc-4.4 /somepath/gccfornvcc/gcc
Then, in the same folder where the nvcc binary lives, you should find a file called nvcc.profile . There you just need to add the following line:
compiler-bindir = /somepath/gccfornvcc
And that will make nvcc use the proper compiler. This helps keeping the system in a proper state, keeping the newest compiler, but nvcc (only nvcc) will use the old compiler version.
Doing some research online shows several methods for accomplishing this task. I just tested the method found here: http://www.vectorfabrics.com/blog/item/cuda_4.0_on_ubuntu_11.04 and it worked like a charm for me. It steps you through installing gcc 4.4 and creating scripts to run that version with nvcc. If you prefer trying the method mentioned in your post I'd recommend following that first link to install gcc4.4 and then create symbolic links as mentioned in your post. Creating symbolic links in Linux is accomplished by using the 'ln' command.
For example:
ln -s [source file/folder path] [linkpath]
This link gives a few examples of creating symbolic links on both Ubuntu and Windows: http://www.howtogeek.com/howto/16226/complete-guide-to-symbolic-links-symlinks-on-windows-or-linux/. Hopefully that points you in the right direction.
I guess you may try the new, beta, version, that based on LLVM.
Another way to make nvcc work with non-default compiler (unlike #Sluml's answer, it allows more flexibility):
At first, just like #Slump proposed, you need to create directory ~/local/gcc-4.4/, and then create there symlinks for right versions of gcc: for i in gcc gxx; do ln -s /usr/bin/${i}-4.4 ~/local/cudagcc/${i}; done. Now when you run nvcc -ccbin ~/local/gcc-4.4/ ... nvcc will use correct versions of gcc.
Here is small CMake snippet of forcing nvcc use specific host compiler.
option (CUDA_ENFORCE_HOST_COMPILER "Force nvcc to use the same compiler used to compile .c(pp) files insted of gcc/g++" OFF)
if (${CUDA_ENFORCE_HOST_COMPILER})
set (CMAKE_GCC_TEMP_DIR "CMakeGCC")
file(MAKE_DIRECTORY ${CMAKE_GCC_TEMP_DIR})
execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink ${CMAKE_C_COMPILER} ${CMAKE_GCC_TEMP_DIR}/gcc)
execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink ${CMAKE_CXX_COMPILER} ${CMAKE_GCC_TEMP_DIR}/g++)
set(CUDA_NVCC_FLAGS -ccbin ${CMAKE_GCC_TEMP_DIR} ${CUDA_NVCC_FLAGS})
endif()
Reference：
I update my gcc from 4.4 to 4.6. Then I could not use nvcc to compile my code. Luckily, by using the method provided by the following link. I set my default gcc compiler back to gcc 4.4. Now, I could compile file using either gcc4.4 or gcc4.6. quit cool
http://ubuntuguide.net/how-to-install-and-setup-gcc-4-1g4-1-in-ubuntu-10-0410-10
I am new to Cuda, and I am trying to compile this simple test_1.cu file:
#include <stdio.h>
__global__ void kernel(void)
{
}
int main (void)
{
kernel<<<1,1>>>();
printf( "Hello, World!\n");
return 0;
}
using this: nvcc test_1.cu
The output I get is:
In file included from /usr/local/cuda/bin/../include/cuda_runtime.h:59:0,
from <command-line>:0:
/usr/local/cuda/bin/../include/host_config.h:82:2: error: #error -- unsupported GNU version! gcc 4.5 and up are not supported!
my gcc --version:
gcc (Ubuntu/Linaro 4.6.1-9ubuntu3) 4.6.1
Copyright (C) 2011 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
How can I install a second version of gcc (4.4 -) along with 4.6 without messing everything up?
I found this old topic:
CUDA incompatible with my gcc version
the answer was:
gcc 4.5 and 4.6 are not supported with CUDA - code won't compile and
the rest of the toolchain, including cuda-gdb, won't work properly.
You cannot use them, and the restriction is non-negotiable.
Your only solution is to install a gcc 4.4 version as a second
compiler (most distributions will allow that). There is an option to
nvcc --compiler-bindir which can be used to point to an alternative
compiler. Create a local directory and the make symbolic links to the
supported gcc version executables. Pass that local directory to nvcc
via the --compiler-bindir option, and you should be able to compile
CUDA code without effecting the rest of your system.
But I have no idea how to do it
In my case I didn't have root rights, so I couldn't fully replace the current gcc (4.7) with the older version 4.4 (which I think would be a bad alternative). Although I did have rights where CUDA was installed. My solution was to create an extra folder (e.g. /somepath/gccfornvcc/), wherever I had rights, then to create a link to an nvcc accepted compiler. I already had gcc 4.4 available (but you can install it, without removing your current version).
ln -s [path to gcc 4.4]/gcc-4.4 /somepath/gccfornvcc/gcc
Then, in the same folder where the nvcc binary lives, you should find a file called nvcc.profile . There you just need to add the following line:
compiler-bindir = /somepath/gccfornvcc
And that will make nvcc use the proper compiler. This helps keeping the system in a proper state, keeping the newest compiler, but nvcc (only nvcc) will use the old compiler version.
Doing some research online shows several methods for accomplishing this task. I just tested the method found here: http://www.vectorfabrics.com/blog/item/cuda_4.0_on_ubuntu_11.04 and it worked like a charm for me. It steps you through installing gcc 4.4 and creating scripts to run that version with nvcc. If you prefer trying the method mentioned in your post I'd recommend following that first link to install gcc4.4 and then create symbolic links as mentioned in your post. Creating symbolic links in Linux is accomplished by using the 'ln' command.
For example:
ln -s [source file/folder path] [linkpath]
This link gives a few examples of creating symbolic links on both Ubuntu and Windows: http://www.howtogeek.com/howto/16226/complete-guide-to-symbolic-links-symlinks-on-windows-or-linux/. Hopefully that points you in the right direction.
I guess you may try the new, beta, version, that based on LLVM.
Another way to make nvcc work with non-default compiler (unlike #Sluml's answer, it allows more flexibility):
At first, just like #Slump proposed, you need to create directory ~/local/gcc-4.4/, and then create there symlinks for right versions of gcc: for i in gcc gxx; do ln -s /usr/bin/${i}-4.4 ~/local/cudagcc/${i}; done. Now when you run nvcc -ccbin ~/local/gcc-4.4/ ... nvcc will use correct versions of gcc.
Here is small CMake snippet of forcing nvcc use specific host compiler.
option (CUDA_ENFORCE_HOST_COMPILER "Force nvcc to use the same compiler used to compile .c(pp) files insted of gcc/g++" OFF)
if (${CUDA_ENFORCE_HOST_COMPILER})
set (CMAKE_GCC_TEMP_DIR "CMakeGCC")
file(MAKE_DIRECTORY ${CMAKE_GCC_TEMP_DIR})
execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink ${CMAKE_C_COMPILER} ${CMAKE_GCC_TEMP_DIR}/gcc)
execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink ${CMAKE_CXX_COMPILER} ${CMAKE_GCC_TEMP_DIR}/g++)
set(CUDA_NVCC_FLAGS -ccbin ${CMAKE_GCC_TEMP_DIR} ${CUDA_NVCC_FLAGS})
endif()
Reference：
I update my gcc from 4.4 to 4.6. Then I could not use nvcc to compile my code. Luckily, by using the method provided by the following link. I set my default gcc compiler back to gcc 4.4. Now, I could compile file using either gcc4.4 or gcc4.6. quit cool
http://ubuntuguide.net/how-to-install-and-setup-gcc-4-1g4-1-in-ubuntu-10-0410-10
I have been trying to install Haskell Platform and cabal-install installed on Linux in user-space on a system that doesn't have the GNU Multi-Precision package (GMP) installed.
I managed to get GHC-6.12.1 installed and GHCi working by setting up LB_LIBRARY_PATH to point at the lib directory where I installed GMP, but then ran into problems in the next step, getting cabal-install to work. It kept trying to (statically) link to GMP.
This fails because the GMP is not installed in the system and ld hasn't a clue where to find the libraries, and there is no environment variable (that I am aware of) that can tell ld where to find the user-installed GMP, and (apparently) no way of telling configuring Cabal to supply the relevant -L flag.
After much fruitless searching and hacking attempts I hit on the absurdly simple idea of installing my own ld shell script that invokes the system ld with the appropriate -L flag.
This is shell scripting 101, of course:
#!/bin/sh
/usr/bin/ld -L$HOME/gnu/lib "$#"
With this script installed in a directory on my PATH ahead of /usr/bin all the problems seem to have gone away.
Basically, your ghc is not working yet. Yes, it can compile things, but it cannot link programs because it needs to link them to gmp.
What we can do is to edit some core package, e.g. the rts package, so that ghc will always use the right -L flag:
ghc-pkg describe rts > rts.pkg
vi rts.pkg # add the gmp dir to the `library-dirs` field
sudo ghc-pkg update rts.pkg