I need to build KLEE on my Ubuntu 12.04. I followed KLEE website's instructions step by step. I had LLVM 2.9 built. But when I need to install klee-uclibc, and in the process of configuring, it complained that it failed to find a working LLVM bitcode compiler. Does this mean that my LLVM built was unsuccessful? I am new to Linux and new to the testing tool. Any help is greatly appreciated.
I ran into the same problem, but a closer look in klee document helped me fix it. Especially look at step (02)(01):
Install llvm-gcc:
Download and install the LLVM 2.9 release of llvm-gcc from here. On an x86-64 Linux platform you are going to need the archive LLVM-GCC 4.2 Front End Binaries for Linux x86-64.
Add llvm-gcc to your PATH. It is important to do this first so that llvm-gcc is found in subsequent configure steps. llvm-gcc will be used later to compile programs that KLEE can execute. Forgetting to add llvm-gcc to your PATH at this point is by far the most common source of build errors reported by new users.
Hence, make sure that llvm-gcc is installed and a PATH is provided to the executable.
Related
I am learning LLVMand C++, but I find it hard to import LLVM into my project.
The first problem is my system has already installed clang and clang++ in usr/bin, but the other LLVM which was installed by brew is in /opt/homebrew/opt/llvm, is ok to delete clang in usr/bin and add opt/homebrew/opt/llvm/bin to env variable?
The second problem is how to link LLVM to my VSCode project, I try link LLVM by
#include "/opt/homebrew/opt/llvm/include/llvm/IR/Constants.h"
but it can't work.
Thanks for any help !!!
Never delete system utilities. Of any kind. For any reason.
Read the information presented to you in brew info llvm. This information was shown to you when you installed it.
Don't #include absolute paths.
Learn how to use compiler/linker flags to tell your compiler where to find headers/libraries.
Read the libc++ documentation to learn how to specify a specific libc++.
Finally, use a tool like cmake to automate this for you.
A homespun makefile might be sufficient.
What you are attempting to do is highly non-trivial. As one of the comments suggests, I would also recommend getting familiar with what's baked in before you try switching to a custom version.
I want to install LLVM 13.0.1 in my local windows (64 bit) system to use it for creating a working enviorment for open source project. I downloaded and install from here but I found it is not complete It is missing many library files and cmake files that are required and getting errors while building. so I want now to install LLVM 13.0.1 from source.
I am very early in learning LLVM , Clang so don't have any idea of doing so. Can anyone give me the entire step / commands to do so.
I'm trying to build a project which is originally written for archlinux. The building process works fine on that archlinux but has a huge amount of errors when I tried to build it on my mac. The project is basically written in C++11 so it's very unstable. I think there has something to do with the compiler because the clang version in mac is 4.2(It actually shows 'Apple LLVM version 4.2 (clang-425.0.28) (based on LLVM 3.2svn)' when I type clang --version) and 3.3 for linux. So I want a different version of clang, perhaps 3.3. How Can I specify the version of my compiler when trying to build the project?
Some might argue this belongs on apple.stackexchange.com, but I'm not sure C++11 tags grab a lot of attention there:)
Xcode 5.0 is now available from the App Store. Install it, go to Preferences -> Downloads, and install the Command Line Tools. However...
First, you will need to go to Preferences -> Accounts and add your Apple ID. For some reason, the Command Line Tools download requires an account login. I don't know what the rationale for this is.
> clang -v
Apple LLVM version 5.0 (clang-500.2.75) (based on LLVM 3.3svn)
If you are willing to build from the command line, using make for example (which sounds likely given the project is from Linux), then install Macports and install whatever version of clang you would like:
$sudo port install clang-3.1
$sudo clang_select
Note that this version of clang shouldn't interfere with the Xcode Command Line package if you are will to invoke the Xcode version using xcrun clang instead of plain old clang.
Here's my problem: I want to use C++11 features provided by either gcc or clang. However, I have these requirements:
I'm using a mac
I'm dependent on a bunch of libraries provided by homebrew (and really don't want to compile them myself). Specifically OSG, which itself is dependent on a ton of other libraries. And boost, though I can always compile that myself.
Homebrew seems to only want to use gcc (please correct me if I'm wrong). I can't find any options to switch to LLVM instead. While I understand that this might be due to the fact that not all libraries are compatible with LLVM yet, this would still be a nice feature for those that are.
The version of gcc that comes pre-installed on a mac of gcc is 4.2. gcc 4.2 doesn't have the c++11 features required. I've installed 4.7 via homebrew, but searches for how to set homebrew to use it all say don't do it (gcc 4.2 on the mac is not the vanilla version, so the 4.7 version I got won't be able to compile some things).
My questions are: Does anyone have any suggestions or fixes they have implemented to get around this problem? Should I give up on Homebrew? Does anyone know if Homebrew has a plan to switch to LLVM in the future? Does anyone have any upgrade-plan for how to deal with these incompatibilities?
I don't see how homebrew can continue to depend on gcc 4.2 in the long run, but haven't found any real discussion on this matter.
The default GCC on Mac is not real GCC of GNU. It's LLVM-GCC in fact, which is a branch of GCC. Several years ago, LLVM-GCC was terminated, and replaced with DragonEgg, which is a GCC plugin to use LLVM as a GCC backend.
LLVM-GCC is just a compiler frontend, whose role is using GCC frontend to translate the source code into LLVM IR[Intro to LLVM 11.3]. Once IR generated, LLVM backend will use it to generate binary code. This step has nothing to do with GCC.
The above goal was fully achieved from 10.7, whose components were all compiled by clang, a frontend provided by LLVM.
But Apple still kept LLVM-GCC and GCC runtime libraries. I guess its purpose might be providing a opportunity to compile some code GCC ONLY.
Now let's answer your questions:
If you want to use C++11 features, use clang++ -stc=c++11 -stdlib=libc++ instead. And clang might have already supported all c++11 features.
If you want homebrew supporting LLVM, it has already supported, at least on backend.
If you want homebrew using clang as a compiler frontend, it depends on homebrew community schedule. For example, you can append --with-c++11 argument to use clang to compile boost.But you cannot use this argument when brew install autoconf. In fact, some components might not be compiled correctly by clang.
If you know it can be compiled by clang but homebrew hasn't supported yet, you have to hack the corresponding ruby script at $HOMEBREW_ROOT/Library/Formula directory. Fortunately, in most of cases, replacing ./configure blablabla with ./configure blablabla CXX=clang++ -stc=c++11 -stdlib=libc++ works well. And by the way, if your hack is successful, please make a pull request to homebrew.
So, try it and have a fun.
I have an OS X Mountain Lion environment and use C++11. In this answer I'll break your requirement for not compiling your own stuff.
I use Homebrew and, I must say, I advise you to give up on depending on it to provide you clang and libc++ and all its formulas built with them.
What I've done, and I like, is
clone llvm, clang and libc++ from repositories.
install to /opt/local and put /opt/local/bin at top on /etc/paths.
build my development stuff with my new clang.
let Homebrew for installing tools like git and things I'll not develop for, just use.
I've followed clang build instructions for installing it to /opt/local.
For libc++, one detail: after running the buildit script, I've symlinked the include directory to /opt/local/lib/c++/v1 (clang on /opt/local looks for this as default directory), and also symlinked the libs to /opt/local/lib/ (but look that binaries will not automatically link to libc++ on /opt/local/lib. You must use install_name_tool for that).
use
clang++ -std=c++11 -stdlib=libc++
you can also install latest gcc from homebrew-dups
brew install [flags] https://raw.github.com/Homebrew/homebrew-dupes/master/gcc.rb
For LLVM, brew install --HEAD llvm. To use clang or a brew-installed gcc, add --with-clang or --with-gcc=gcc-x.x where x.x is the version you want.
I am trying to compile a 32-bit version (MinGW) of a program I wrote using zlib. Until now, I've never has to compile for 32-bit so the version of zlib I compiled from source (libz.a) is 64-bit. I tried to rerun the makefile in the zlib-1.2.5 directory but it only compiles a 64bit version of libz.a.
I can't seem to find an option to build 32-bit.
Does anyone know how to do this?
Thanks!
Jeffrey Kevin Pry
Checking the configure file, you can see some env.
On 64bit debian, following command line will build the 32bit version of libz
CFLAGS=-m32 ./configure
It turns out I had to get the 32bit version of MinGW and compile it with that. I was using MinGW64.
Using CFLAGS=-32 won't do it for me, configure script still shouts out telling me to use win32/Makefile.gcc instead all the time.
The recent version of zlib is 1.2.11, so it should be minimal gap of difference up until today. Without any context on system, the following might be useful for other users facing this similar problem these days.
I cross compile on Linux (Ubuntu 18.04), and target 32-bit version of zlib to be produced. What I did is as follows.
./configure (this is just to let us have required file to building process, we will be using different Makefile though)
Modify win32/Makefile.gcc for its PREFIX=i686-w64-mingw32- (for 64-bit you change it to PREFIX=x86_64-w64-mingw32-.
make -fwin32/Makefile.gcc
Install to your desire location via make install -fwin32/Makefile.gcc SHARED_MODE=1 INCLUDE_PATH=/tmp/zlib-win32/include LIBRARY_PATH=/tmp/zlib-win32/lib BINARY_PATH=/tmp/zlib-win32/bin. Notice that you need to specify INCLUDE_PATH, LIBRARY_PATH, and BINARY_PATH. BINARY_PATH will contains result .dll file.