I'm attempting to essentially follow the llvm Kaleidoscope example.
I'm on Windows. I built llvm from source per the directions on the site. It took quite a long time but it finally built successfully (no errors at least).
Then with my own code I am running this command:
$ clang-cl main.obj llvm/lib/LLVMCore.lib llvm/lib/LLVMSupport.lib /MDd -o build\test.exe
My main.cpp code has this in it:
#include "llvm/ADT/STLExtras.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Verifier.h"
std::unique_ptr<Module> module = llvm::make_unique<Module>("my cool jit", getGlobalContext());
And I'm not getting any parser errors but I am getting an error from the linker that for the life of me I cannot figure out:
LLVMSupport.lib(Path.obj) : error LNK2019: unresolved external symbol
__imp_CoTaskMemFree referenced in function "bool __cdecl
llvm::sys::path::getKnownFolderPath(struct _GUID,class
llvm::SmallVectorImpl<char> &)" (?
getKnownFolderPath#path#sys#llvm##YA_NU_GUID##AEAV?$SmallVectorImpl#D#3##Z)
build\test.exe : fatal error LNK1120: 1 unresolved externals
Which library do I have to link to for this function to be defined? I can see the implementation in the code I built from. Do I need to build llvm in a particular way for this to be exported?
EDIT:
It turns out that I needed to read the clang-cl documentation a little better where it says:
To enable clang-cl to find system headers, libraries, and the linker when run from the command-line, it should be executed inside a Visual Studio Native Tools Command Prompt or a regular Command Prompt where the environment has been set up using e.g. vcvars32.bat.
It turns out that this solves my problem. I was a little confused because clang-cl seems to resolve the sdk include and tool paths automatically, but not the lib paths. I also don't want to use CMD to drive clang so I was using bash where I can't run vcvar32.bat easily. I solved my problem by essentially duplicating what vcvar32.bat is doing to the $PATH, $INCLUDE, $LIB and $LIBPATH environment variables and adding Ole32.Lib as a parameter to clang-cl. It then works like a charm.
You're missing the CoTaskMemFree symbol. A quick look on the Internet suggests you'll need the Ole32 system library on your link line.
I don't have access to a Windows machine to test on, but on my computer, I can run llvm-config --system-libs and it pulls in the all the necessary things. After adding using namespace llvm; and adding a stub main function, I can easily build this example with (on OSX):
c++ `llvm-config --cxxflags` main.cpp `llvm-config --ldflags --system-libs --libs core support`
I often recommend just specifying --libs rather than guessing what you'll need, but your choice.
Related
I am currently using clang11 on ubuntu to compile any c/c++ code and it works fine but when I tried to compile any code (including any standard library) to assembly code for any specific target like x86_64 (even I have x86_64) riscv with giving a flag that --target=x86_64 or --target=riscv32 I got errors for any standard library that I included in my code. A simple example:
// ex.cpp
#include<iostream>
int main(){
int a = 5;
int b = 3;
std::cout << a - b;
}
Without giving flag for a spesific target works fine:
clang++-11 -S ex.cpp -o ex.s
With --target=riscv32 flag:
clang++-11 --target=riscv32 -S ex.cpp -o ex.s
gives this error:
ex.cpp:1:9: fatal error: 'iostream' file not found
also without standard libraries gives no error even I give a spesific target.
I am searching for a solution for days but I couldn't find any proper solution for this problem, most of them says try to include gnu libraries and subfolders like -I/usr/include/x86_64-linux-gnu/c++/ but it doesn't work for me.
Please don't say use g++ compiler, for adding an optimization I need clang.
Actually I am trying to compile my codes for riscv target, linking with g++ and running with spike (doesn't differ --target=... or -target ...):
clang++-11 -target riscv32-unknown-elf -march=rv32gc -fno-addrsig -S ex.cpp -o ex.s
~/riscv/bin/riscv32-unknown-elf-g++ ex.s -o ex
~/riscv/riscv-isa-sim/build/spike --isa=RV32GC ~/riscv/riscv-pk/build/pk ex
And it works fine without include a standard library.
Now, I want to ask that
Can I solve this problem simply?
or
Can I use clang directly from riscv bin utils like ~/riscv/bin/riscv32-unknown-elf-clang++ (I saw something like this on the net but couldn't find) adding and building a submodule to my riscv directory?
Edit: As #NateEldredge said, for x86_64 target triple should --target=x86_64-linux-gnu but for riscv as a target triple riscv32-unknown-elf I still have the same errors. Is there a proper target flag for riscv any other than --target=riscv32-unknown-elf? Maybe I am missing that point.
I solved my problem by linking compilations with riscv-gnu-toolchain built and also answered a similar question here in detailed: Using Clang to compile for RISC-V
Simply we need cross-compilation.
Further information you can also look here: https://github.com/lowRISC/riscv-llvm#how-can-i-build-upstream-llvmclang-and-use-it-to-cross-compile-for-a-riscv32-target
I am trying to compile a minimal C++ code
#include <iostream>
#include <mkl.h>
#include <omp.h>
int main(int argc, char *argv[])
{
omp_set_num_threads(4);
return 0;
}
using the MKL library (icc version 17.0.4) in a MacOSX Sierra 10.12.5, using the command
icc main.cpp -o main.o -DMKL_ILP64 -I/opt/intel/compilers_and_libraries_2017.4.181/mac/mkl/include \
-L/opt/intel/compilers_and_libraries_2017.4.181/mac/mkl/lib -Wl,-rpath,/opt/intel/compilers_and_libraries_2017.4.181/mac/mkl/lib -lmkl_intel_ilp64 \
-lmkl_intel_thread -lmkl_core -liomp5 -lpthread -lm -ldl
However I receive the following error when I run the program
dyld: Library not loaded: #rpath/libiomp5.dylib
Referenced from: /Users/user/C++/MKL1/./main.o
Reason: image not found
/bin/sh: line 1: 8898 Abort trap: 6 ./main.o
make: *** [run] Error 134
How to set up properly the openmpi with the MKL library? I tried to follow the instruction in https://software.intel.com/en-us/articles/dyld-library-not-loadedlibiomp5dylib?page=1#comment-1905809
by adding
source /opt/intel/compilers_and_libraries_2017.4.181/mac/mkl/bin/mklvars.sh intel64
However I still get the same error during runtime.
I have tried a few ways to solve this issue. It literally took an entire day. But here are the results,
Project Files
I created a very simple Project with just one file, named,
test.c
1. The Easiest Solution
Fixing this can be as simple as,
icc -qopenmp -qopenmp-link=static test.c
This method just tells the compiler to link to static OpenMP run-time libraries.
Interestingly, the docs at Intel C++ Compiler Docs v.15 say that this is deprecated while Intel C++ Compiler Docs v.17 do not even mention about this argument, BUT it works. Probably they forgot to take it out.
2. Another method (which I do not recommend, nor do folks at Intel)
To compile the file you can use the normal "-qopenmp" flag
icc -qopenmp test.c
This creates the "a.out" file.
This method of fixing the error makes use of command-line utility called,
install_name_tool
Using this method we can change the path of #rpath/libiomp5.dylib
install_name_tool -change #rpath/libiomp5.dylib /opt/intel/compilers_and_libraries_2018.1.126/mac/compiler/lib/libiomp5.dylib a.out
Note: In place of compilers_and_libraries_2018.1.126 it should be your version of the compiler.
3. One of the BEST (correct) ways
You can just add
export DYLD_LIBRARY_PATH="/opt/intel/compilers_and_libraries_2018.1.126/mac/compiler/lib"
To your ~/.bash_profile
And then use the normal way of compiling,
icc -qopenmp test.c
Everything works perfectly.
Quick tip: You can use the otool command line utility to check the libraries your file links to.
otool -L a.out
I found the answer on https://software.intel.com/en-us/forums/intel-fortran-compiler-for-linux-and-mac-os-x/topic/645194
Basically one has to add
-Wl,-rpath,/opt/intel/compilers_and_libraries_2017.4.181/mac/compiler/lib
during compilation. Now openmp with icc works perfectly
I've recently built libc++ from scratch as my prject needs some features that are not yet implemnted in libstdc++.
I try to compile the hello world program located in src/main.cpp with line
clang -Wall -stdlib=libc++ -std=c++11 -c src/main.cpp -obuild/main.o
and the build suceeds
Then I link it with
clang -lc++ build/main.o -o qasix
and the linking suceeds too.
But when I run the program with
./qasix
I get the following error:
./qasix: symbol lookup error: /usr/local/lib/libc++.so.1: undefined symbol: _ZTVN10__cxxabiv120__si_class_type_infoE
I would like to know why this is occurring and also how to fix it.
I am on Xubuntu 13.10 if that's of any help.
PS: This problem popped up yesterday. Earlier other libc++ programs would compile fine.
This started when I did a debug build of a program with the -g flag and it compiled and ran fine, but all later programs complained about this symbol lookup failure. Please help.
it appears that you need the support library "libc++abi". It provides things like low-level exception support, type_info support, etc.
For Ubuntu (as opposed to Xubuntu), it appears that you can get it here: http://www.ubuntuupdates.org/package/core/saucy/universe/base/libc++abi-dev
I've been working on this for a while now, and can't seem to make sense of the situation - partly bceause I don't fully understand what's going on (which is why I came here).
I'm doing a sort of boost hello world as follows:
#include <boost/thread/thread.hpp>
#include <cstdio>
void helloworld() {
std::printf("HELLO FROM A BOOST THREAD!");
}
int main(int argc, char **argv) {
boost::thread t(&helloworld);
t.join();
}
This is on Windows. I stored the Boost directory in C:\Boost. I ran bootstrap and bjam, and now have a stage/lib folder that contains all the .lib files. The lib files relating to the boost/thread library are:
libboost_thread-vc100-mt.lib
libboost_thread-vc100-mt-1_46_1.lib
libboost_thread-vc100-mt-gd.lib
libboost_thread-vc100-mt-gd-1_46_1.lib
Now I compile:
g++ -c main.cpp -I/Boost
that line works fine, I get main.o. Then:
g++ -o test.exe main.o -L/Boost/stage/lib -llibboost_thread-vc100-mt
And that's where the trouble happens. First of all, If I didn't type the -l argument the way I did, MinGW couldn't even find the file. Meaning, if I tried:
-lboost_thread-vc100-mt
instead of the way I typed it above (and how I thought it should be done), ld would exit with no such file. Anyway, this is now the output I'm getting from that line:
main.o:main.cpp:(.text+0x47): undefined reference to `_imp___ZN5boost6thread4joinEv'
main.o:main.cpp:(.text+0x55): undefined reference to `_imp___ZN5boost6threadD1Ev'
main.o:main.cpp:(.text+0x70): undefined reference to `_imp___ZN5boost6threadD1Ev'
main.o:main.cpp:(.text$_ZN5boost6threadC1IPFvvEEET_NS_10disable_ifINS_14is_convertibleIRS4_NS_6detail13thread_move_tIS4_EEEEPNS0_5dummyEE4typeE[boost::thread::thread<void (*)()>(void (*)(), boost::disable_if<boost::is_convertible<void (*&)(), boost::detail::thread_move_t<void (*)()> >, boost::thread::dummy*>::type)]+0x23): undefined reference to `_imp___ZN5boost6thread12start_threadEv'
collect2: ld returned 1 exit status
Now somewhere in there, I can tell that these are apparently the functions I'm supposed to be getting from boost/thread, and apparently it does find the lib file, so why isn't it linking correctly?
Thank you very much for any help!
EDIT:
I've rebuilt boost using the bjam "stage" option
bjam toolset=gcc stage
Now, after the build completes, I'm left with a stage/lib folder with .a files, as is to be expected. These are the boost/thread related libraries:
libboost_thread-mgw45-mt-1_46_1.a
libboost_thread-mgw45-mt-d-1_46_1.a
However, linking as follows:
g++ -o test.exe main.o -L/Boost/stage/lib -lboost_thread-mgw45-mt-1_46_1
outputs the exact same errors. Also tried:
g++ -o test.exe main.o -L/Boost/stage/lib -lboost_thread-mgw45-mt-1_46_1 -static
I'm at a loss, still.
Solved the problem. Boost's headers are configured to be dynamically linked, but the dynamic libraries (dll's) are not built unless you specify:
--build-type=complete
when invoking bjam. After that, copy the appropriate dll to your application directory, but still use the
-L/BOOST_DIR/stage/lib -lname
when linking.
This set of library files:
libboost_thread-vc100-mt.lib
libboost_thread-vc100-mt-1_46_1.lib
libboost_thread-vc100-mt-gd.lib
libboost_thread-vc100-mt-gd-1_46_1.lib
are for the Visual Studio 2010 compiler. They won't work with GCC. If you want to use gcc/MinGW, you'll need to download/build a set of boost libraries for that compiler. Alternatively you can install VS 2010 and use that compiler (the free VC++ 2010 Express version should work fine if cost is an issue).
You can get a MinGW distribution with Boost already in the package from http://nuwen.net/mingw.html (32-bit target only, I believe).
To answer about getting the errors with using the MinGW libs:
The _imp_ prefixes on the symbols is an indication that g++ is looking to link to a a dll/shared library. The .lib file you have are for static libraries (which is what also what I get when doing a straightforward bjam build of the libraries). If you look in boost/thread/detail/config.hpp you'll see that for Win32 builds it defaults to building against a DLL library unless the MSVC or Intel compiler is being used.
I'm not even sure exactly how to build the DLL libraries - I'll have to look it up. In the meantime, you can use the following command to build your example such that it'll link against the static library. The BOOST_THREAD_USE_LIB macro build the .cpp file such that it'll expect to link against the static library:
g++ -I/Boost -DBOOST_THREAD_USE_LIB -c main.cpp
I am have been attempting to get a C++ project setup using boost file system library using eclipse. I followed these directions to install boost on my system. The directions where pretty much
download
extract
run bootstrap.sh
run ./bjam architecture=combined
That seemed to go fine, no errors. I then fired up eclipse and created a new test project called test with a single file called test.cpp. The code in it is:
#include <stdio.h>
#include <boost/filesystem.hpp>
int main() {
boost::filesystem::path path("/Users/schoen"); // random pathname
bool result = boost::filesystem::is_directory(path);
printf("Path is a directory : %d\n", result);
return 0;
}
This is just something simple to make sure it is all set up correctly. Of course I tried to compile at this point and it failed. Did some googling and found this site. It said to add the boost library to the linker by going to project properties and adding "boost_filesystem". I tried this, and well it didn't work.
Can someone point me in the right direction or give me a hint to how to set up Boost in an Eclipse project?
I am new to C++ and Eclipse, and most my experience is in Java with Netbeans. So I am pretty lost at the moment.
UPDATE
I just wanted to update on what I have tried based on the answers given.
Based on Alex's suggestion I added boost_system and boost_filesystem to the linker list. I was still getting the same compiler errors.
Following the suggestion from rve I added the path to the boost libraries to the Library search path. When this did not work. I cleared out the linker list and tried it with just the library search path. This also did not work.
I then cleared the Library search path. I then manually edited the command on the linker window to be 'g++ -L/Users/jacobschoen/Library/boost_1_45_0/stage/lib -lboost -lboost_filesystem'. This also did not work.
In all of these I tried setting the path to boost to be '/Users/jacobschoen/Library/boost_1_45_0' and '/Users/jacobschoen/Library/boost_1_45_0/stage/lib'. Neither worked.
As requested the comiler error for the above code is:
**** Build of configuration Debug for project test ****
make all
Building file: ../src/test.cpp
Invoking: GCC C++ Compiler
g++ -O0 -g3 -Wall -c -fmessage-length=0 -MMD -MP -MF"src/test.d" -MT"src/test.d" -o"src/test.o" "../src/test.cpp"
../src/test.cpp:10:32: warning: boost/filesystem.hpp: No such file or directory
../src/test.cpp: In function 'int main()':
../src/test.cpp:13: error: 'boost' has not been declared
../src/test.cpp:13: error: expected `;' before 'path'
../src/test.cpp:14: error: 'boost' has not been declared
../src/test.cpp:14: error: 'path' was not declared in this scope
make: *** [src/test.o] Error 1
If any one has any further suggestions I am still trying.
Second Update
On a suggestion by rholmes I added an include library along with the linker list and library search path. So now the compile error is:
**** Build of configuration Debug for project test ****
make all
Building target: test
Invoking: MacOS X C++ Linker
g++ -L/Users/jacobschoen/Library/boost_1_45_0 -o "test" ./src/test.o -lboost_system -lboost_filesystem
ld: library not found for -lboost_system
collect2: ld returned 1 exit status
make: *** [test] Error 1
Any ideas?
Just wanted to be clear on what actually worked, since it was kinda pieced together from a few answers.
Download the boost files and extract them to where you want to put them.
In your terminal navigate to the directory and run ./bootstrap.sh
When that is done run ./bjam (this takes a while so go smoke and get a cup of coffee)
Open up your eclipse Project and go to Project > Properties > C/C++ Build > Settings
Click on MacOS X C++ Linker > Libraries.
You should see a split window with the top being for 'Libraries (-l)'. In this section add both boost_system and boost_filesystem. In the bottom section it should be for 'Library Search Path (-L)'. Here you want to put the path to the stage/lib directory inside where you extracted the boost download. It should look similar to below:
Click GCC C++ Compiler > Includes. This will be a single pane where it says 'Include Paths (-I)', well I think it is an I as he font is weird and could be a lower case l also. Anyway in that section add the path to where you put boost without the stage/lib part. It should look like below:
Everything should compile now with out a problem, and if you need to use any other boost libraries it should be just a matter of adding it to the linker section where boost_filesystem and boost_system are. Enjoy.
Not sure where you do this in Eclipse these days, but under the include paths for Eclipse should be the path to the main boost directory (/Users/jacobschoen/Library/boost_1_45_0?). The compiler line should have something like the following in it, I would think:
Invoking: GCC C++ Compiler
g++ -I/Users/jacobschoen/Library/boost_1_45_0 -O0 -g3 -Wall -c -fmessage-length=0 -MMD (etc..)
Update: Looking at my system, the linker path on yours might be more appropriately:
-I/Users/jacobschoen/Library/boost_1_45_0/stage/lib
Depending, of course, upon how you've installed and built boost -- this is with my most recent attempt with a full source build. Depending upon how you obtained boost, this may or may not be different. I recently redid the boost on my Mac for 64 bit and haven't had much time to try it yet....
Add boost_system to the linker list, together with boost_filesystem.
I had recently uninstalled the boost rpm and installed Boost like how you did. I had no problems running Boost programs in Eclipse. I didn't add any extra parameters. Just installed boost and ran Boost programs. It works fine.
Tried your program in the vi editor. Commented out everything in main
#include <cstdio>
#include <boost/filesystem.hpp>
int main() {
/*boost::filesystem::path path("/Users/schoen"); // random pathname
bool result = boost::filesystem::is_directory(path);
printf("Path is a directory : %d\n", result);*/
return 0;
}
and it still gave this error:
/tmp/cc7TAIYS.o: In function `__static_initialization_and_destruction_0(int, int)':
test.cpp:(.text+0x29): undefined reference to `boost::system::get_system_category()'
test.cpp:(.text+0x35): undefined reference to `boost::system::get_generic_category()'
test.cpp:(.text+0x41): undefined reference to `boost::system::get_generic_category()'
test.cpp:(.text+0x4d): undefined reference to `boost::system::get_generic_category()'
test.cpp:(.text+0x59): undefined reference to `boost::system::get_system_category()'
collect2: ld returned 1 exit status
I'm puzzled. Boost programs work on my system, but your program's header files itself are giving a problem. I doubt it's a problem with Eclipse. It has to be something else.
I just ran into something very similar to this using eclipse and CDT... It turns out, using ubuntu and apt-get, libboost_system installs as libboost_system.1.40.0 in /usr/lib
If you try to add it via the library tab in Helios it will complain because it is looking for *.so and *.s0.1.40.0 clearly doesn't match that. However after looking closely at what the linker was trying to doo, I just typed the raw string "boost_system" into the include path adder. This resulted in the linker doing a " -lboost_system" which is a format the linker knows how to deal with in resolving version dependency... If you instead put in the full path to the .so file, the linker will just complain because it tries to do a " -l/usr/lib/libboost_system.so.1.40.0" .
So take my advice and just type in the simple " boost_system" after doing an apt-get install.. It will make it all very easy.