I am new to cmake though not to make. This question is different from Could not build OpenCV Android sample project since that other question is about a single project and this one is looking at the overall CMakeLists.txt.
Speaking of which: consider the CMakeLists.txt in ${OPENCVDIR}/samples :
I followed basic process for cmake:
cd "${OPENCVDIR}/samples"
mkdir build
cd build
cmake ..
But at the last step I have:
$ cmake ..
CMake Error at CMakeLists.txt:72 (find_package):
Could not find a package configuration file provided by "OpenCV" with any
of the following names:
OpenCVConfig.cmake
opencv-config.cmake
Add the installation prefix of "OpenCV" to CMAKE_PREFIX_PATH or set
"OpenCV_DIR" to a directory containing one of the above files. If "OpenCV"
provides a separate development package or SDK, be sure it has been
installed.
-- Configuring incomplete, errors occurred!
See also "/git/opencv/samples/CMakeFiles/CMakeOutput.log".
Line 72 has this: find_package(OpenCV REQUIRED PATHS "..")
I looked at the error log and it was not informative.
Compilation of the CXX compiler identification source "CMakeCXXCompilerId.cpp" produced "a.out"
The CXX compiler identification is GNU, found in "/git/opencv/samples/CMakeFiles/3.13.4/CompilerIdCXX/a.out"
Determining if the C compiler works passed with the following output:
Change Dir: /git/opencv/samples/CMakeFiles/CMakeTmp
Run Build Command:"/usr/bin/make" "cmTC_26f76/fast"
/usr/bin/make -f CMakeFiles/cmTC_26f76.dir/build.make CMakeFiles/cmTC_26f76.dir/build
make[1]: Entering directory '/git/opencv/samples/CMakeFiles/CMakeTmp'
Building C object CMakeFiles/cmTC_26f76.dir/testCCompiler.c.o
/usr/bin/cc -o CMakeFiles/cmTC_26f76.dir/testCCompiler.c.o -c /git/opencv/samples/CMakeFiles/CMakeTmp/testCCompiler.c
Linking C executable cmTC_26f76
/usr/bin/cmake -E cmake_link_script CMakeFiles/cmTC_26f76.dir/link.txt --verbose=1
/usr/bin/cc -rdynamic CMakeFiles/cmTC_26f76.dir/testCCompiler.c.o -o cmTC_26f76
make[1]: Leaving directory '/git/opencv/samples/CMakeFiles/CMakeTmp'
Detecting C compiler ABI info compiled with the following output:
"/git/opencv/samples/CMakeFiles/CMakeOutput.log" 706 lines, 48095 characters
Feature record: CXX_FEATURE:0cxx_defaulted_move_initializers
Feature record: CXX_FEATURE:0cxx_delegating_constructors
Feature record: CXX_FEATURE:0cxx_deleted_functions
Feature record: CXX_FEATURE:0cxx_digit_separators
Feature record: CXX_FEATURE:0cxx_enum_forward_declarations
Feature record: CXX_FEATURE:0cxx_explicit_conversions
Feature record: CXX_FEATURE:0cxx_extended_friend_declar
etc ..
What is the correct way to build these examples - hopefully using the CMakeLists.txt already provided?
It seems the installation directory of OpenCV couldn't be found by cmake. Try to provide the value through the argument:
cmake -DCMAKE_PREFIX_PATH=/home/someone/src/opencv/install ..
Ff it works, you could define this in the top-level CMakeLitst.txt:
list(APPEND CMAKE_PREFIX_PATH /home/someone/src/opencv/install)
This should provide CMake the place where it should look to.
$ opencv_version
3.4.16
$ cd OpenCV/samples/
$ cmake -B build
$ cmake --build build
JPEG display
$ build/cpp/example_cpp_image data/lena.jpg
USB camera capture
$ build/cpp/example_cpp_videocapture_basic
$ build/cpp/example_cpp_videocapture_camera
Recognition by AI
$ build/tapi/example_tapi_hog
Related
Although High Sierra is no longer supported by Homebrew, but I need to install llvm#13 formula as a dependency for other formulas. So I tried to install it this way:
$ brew install llvm
...
==> Downloading https://github.com/llvm/llvm-project/releases/download/llvmorg-13.0.0/llvm-project-13.0.0.src.tar.xz
Already downloaded: /Users/username/Library/Caches/Homebrew/downloads/8fd68fc8f968137c5080826db6e58682326235960fd8469363eb27d0799978ca--llvm-project-13.0.0.src.tar.xz
...
==> Installing llvm
==> cmake -G Unix Makefiles .. -DLLVM_ENABLE_PROJECTS=clang;clang-tools-extra;lld;lldb;mlir;polly -DLLVM_ENABLE_RUNTIMES=compiler-rt;libcxx;libcxxabi;libunwind;openmp -DLLVM_POLLY_L
==> cmake --build .
...
[ 79%] Built target lldELF
make: *** [all] Error 2
An error is occurred after a long time of compilation. I also found this error in ~/Library/Logs/Homebrew/llvm/02.cmake:
/tmp/llvm-20211109-12151-m0zvtm/llvm-project-13.0.0.src/lldb/source/Host/macosx/objcxx/HostInfoMacOSX.mm:246:52: error: use of undeclared identifier 'CPU_SUBTYPE_ARM64E'
if (cputype == CPU_TYPE_ARM64 && cpusubtype == CPU_SUBTYPE_ARM64E) {
^
1 error generated.
make[2]: *** [tools/lldb/source/Host/macosx/objcxx/CMakeFiles/lldbHostMacOSXObjCXX.dir/HostInfoMacOSX.mm.o] Error 1
make[1]: *** [tools/lldb/source/Host/macosx/objcxx/CMakeFiles/lldbHostMacOSXObjCXX.dir/all] Error 2
How can I fix that compilation error?
Install llvm with debug mode enabled:
$ brew install --debug llvm
Installation process encounters with the same error mentioned in the question, but some options are provided to fix the issue. Choose option 5:
- raise
- ignore
- backtrace
- irb
- shell
Choose an action: 5
It gives a shell access to the current build directory of llvm formula. Find the current folder:
$ pwd
/private/tmp/llvm-20211109-12151-m0zvtm/llvm-project-13.0.0.src
Change the location to the build directory:
cd llvm/build
Edit the HostInfoMacOSX.mm and remove the second part of condition:
vi ../../lldb/source/Host/macosx/objcxx/HostInfoMacOSX.mm
You need to change the line 246 from:
if (cputype == CPU_TYPE_ARM64 && cpusubtype == CPU_SUBTYPE_ARM64E) {
to:
if (cputype == CPU_TYPE_ARM64) {
Then re-run the last command:
$ cmake --build .
It takes some time to be completed:
...
[100%] Linking CXX executable ../../../../bin/lldb-vscode
cd /tmp/llvm-20211109-12151-m0zvtm/llvm-project-13.0.0.src/llvm/build/tools/lldb/tools/lldb-vscode && /usr/local/Cellar/cmake/3.21.4/bin/cmake -E cmake_link_script CMakeFiles/lldb-v
scode.dir/link.txt --verbose=1
/usr/local/Homebrew/Library/Homebrew/shims/mac/super/clang++ -stdlib=libc++ -fPIC -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wn
o-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-c
lass-memaccess -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wno-deprecated-declarations -Wno-unkn
own-pragmas -Wno-strict-aliasing -Wno-deprecated-register -Wno-vla-extension -O3 -DNDEBUG -Wl,-search_paths_first -Wl,-headerpad_max_install_names -stdlib=libc++ -Wl,-sectcreate,__
TEXT,__info_plist,/tmp/llvm-20211109-12151-m0zvtm/llvm-project-13.0.0.src/llvm/build/tools/lldb/tools/lldb-vscode/lldb-vscode-Info.plist -Wl,-dead_strip CMakeFiles/lldb-vscode.dir/
lldb-vscode.cpp.o CMakeFiles/lldb-vscode.dir/BreakpointBase.cpp.o CMakeFiles/lldb-vscode.dir/ExceptionBreakpoint.cpp.o CMakeFiles/lldb-vscode.dir/FifoFiles.cpp.o CMakeFiles/lldb-vsc
ode.dir/FunctionBreakpoint.cpp.o CMakeFiles/lldb-vscode.dir/IOStream.cpp.o CMakeFiles/lldb-vscode.dir/JSONUtils.cpp.o CMakeFiles/lldb-vscode.dir/LLDBUtils.cpp.o CMakeFiles/lldb-vsco
de.dir/OutputRedirector.cpp.o CMakeFiles/lldb-vscode.dir/ProgressEvent.cpp.o CMakeFiles/lldb-vscode.dir/RunInTerminal.cpp.o CMakeFiles/lldb-vscode.dir/SourceBreakpoint.cpp.o CMakeFi
les/lldb-vscode.dir/VSCode.cpp.o -o ../../../../bin/lldb-vscode -Wl,-rpath,#loader_path/../lib ../../../../lib/liblldb.13.0.0.dylib -lpthread ../../../../lib/libclang-cpp.dylib ../
../../../lib/libLLVM.dylib
[100%] Built target lldb-vscode
/usr/local/Cellar/cmake/3.21.4/bin/cmake -E cmake_progress_start /tmp/llvm-20211109-12151-m0zvtm/llvm-project-13.0.0.src/llvm/build/CMakeFiles 0
Then run the install command:
$ cmake --build . --target install
The tail of the result should be:
...
-- Installing: /usr/local/Cellar/llvm/13.0.0_1/lib/cmake/llvm/./CheckAtomic.cmake
-- Installing: /usr/local/Cellar/llvm/13.0.0_1/lib/cmake/llvm/./FindSphinx.cmake
-- Installing: /usr/local/Cellar/llvm/13.0.0_1/lib/cmake/llvm/./FindGRPC.cmake
-- Installing: /usr/local/Cellar/llvm/13.0.0_1/lib/cmake/llvm/./TableGen.cmake
Execute the last command:
$ cmake --build . --target install-xcode-toolchain
The tail of the results should be:
...
-- Installing: /usr/local/Cellar/llvm/13.0.0_1/Toolchains/LLVM13.0.0.xctoolchain//usr/lib/cmake/llvm/./CheckAtomic.cmake
-- Installing: /usr/local/Cellar/llvm/13.0.0_1/Toolchains/LLVM13.0.0.xctoolchain//usr/lib/cmake/llvm/./FindSphinx.cmake
-- Installing: /usr/local/Cellar/llvm/13.0.0_1/Toolchains/LLVM13.0.0.xctoolchain//usr/lib/cmake/llvm/./FindGRPC.cmake
-- Installing: /usr/local/Cellar/llvm/13.0.0_1/Toolchains/LLVM13.0.0.xctoolchain//usr/lib/cmake/llvm/./TableGen.cmake
Built target install-xcode-toolchain
/usr/local/Cellar/cmake/3.21.4/bin/cmake -E cmake_progress_start /tmp/llvm-20211109-12151-m0zvtm/llvm-project-13.0.0.src/llvm/build/CMakeFiles 0
Then press control+d to return to debug menu. Because the two last commands were run manually, you need to ignore the rest of errors by choosing the option 2:
- raise
- ignore
- backtrace
- irb
- shell
Choose an action: 2
==> cmake --build . --target install
...
cmake
--build
.
--target
install
Error: could not load cache
BuildError: Failed executing: cmake --build . --target install
1. raise
2. ignore
3. backtrace
4. irb
5. shell
Choose an action: 2
==> cmake --build . --target install-xcode-toolchain
...
cmake
--build
.
--target
install-xcode-toolchain
Error: could not load cache
BuildError: Failed executing: cmake --build . --target install-xcode-toolchain
1. raise
2. ignore
3. backtrace
4. irb
5. shell
Choose an action: 2
It will continue to install to the rest:
==> Fixing /usr/local/Cellar/llvm/13.0.0_1/bin/FileCheck permissions from 755 to 555
==> Fixing /usr/local/Cellar/llvm/13.0.0_1/bin/analyze-build permissions from 755 to 555
...
==> Changing dylib ID of /usr/local/Cellar/llvm/13.0.0_1/lib/libunwind.1.0.dylib
from #rpath/libunwind.1.dylib
to /usr/local/opt/llvm/lib/libunwind.1.dylib
/usr/local/Homebrew/Library/Homebrew/brew.rb (Formulary::FromPathLoader): loading /usr/local/opt/llvm/.brew/llvm.rb
==> Caveats
To use the bundled libc++ please add the following LDFLAGS:
LDFLAGS="-L/usr/local/opt/llvm/lib -Wl,-rpath,/usr/local/opt/llvm/lib"
llvm is keg-only, which means it was not symlinked into /usr/local,
because macOS already provides this software and installing another version in
parallel can cause all kinds of trouble.
If you need to have llvm first in your PATH, run:
echo 'export PATH="/usr/local/opt/llvm/bin:$PATH"' >> ~/.zshrc
For compilers to find llvm you may need to set:
export LDFLAGS="-L/usr/local/opt/llvm/lib"
export CPPFLAGS="-I/usr/local/opt/llvm/include"
==> Summary
đș /usr/local/Cellar/llvm/13.0.0_1: 10,907 files, 1.8GB, built in 1418 minutes 39 seconds
It can be verified this way, the default llvm#10 pre-installed:
$ /usr/bin/clang --version
Apple LLVM version 10.0.0 (clang-1000.11.45.5)
Target: x86_64-apple-darwin17.7.0
Thread model: posix
InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin
And the new Homebrew version of llvm#13:
$ /usr/local/opt/llvm/bin/clang --version
Homebrew clang version 13.0.0
Target: x86_64-apple-darwin17.7.0
Thread model: posix
InstalledDir: /usr/local/opt/llvm/bin
#HamidRohani provides a great solution for those still tinkering in High Sierra (10.13). Getting a recent version of LLVM to compile on my old MAC with an older XCode (clang version 10.0.1 in my case) was a great help. My nominal contribution...
Alternatively, you could define the symbol after line 41 in HostInfoMacOSX.mm:
// Kludge: Symbol definition extracted from a modern machine.h
#ifndef CPU_SUBTYPE_ARM64E
# define CPU_SUBTYPE_ARM64E ((cpu_subtype_t) 2)
#endif
Now, there's no need to modify line 246. And the definition would resolve any (possible) subsequent references. And let me aggregate the steps shown above conducted in brew's debug-shell:
cmake . -DLLVM_CREATE_XCODE_TOOLCHAIN=On
cmake --build .
cmake --build . --target install
cmake --build . --target install-xcode-toolchain
Regarding the LLVM-related variable, setting LLVM_CREATE_XCODE_TOOLCHAIN to On directs CMake to generate a target named 'install-xcode-toolchain'. 1 The target is a work-around to System Integrity Protection (SIP); "Xcode toolchains are a mostly-undocumented feature that allows multiple copies of low level tools to be installed to different locations, and users can easily switch between them." 2
Brew's Caveats
Brew gives you few caveats necessary to use the new compiler: "because macOS already provides this software and installing another version in parallel can cause all kinds of trouble." To use your new compiler, "You need to have llvm first in your PATH and for compilers to find llvm you may need to set" LDFLAGS and CDFLAGS. But since these gems-of-wisdom appear near the end of a million-lines of output, let me re-iterate here:
export PATH="/usr/local/opt/llvm/bin:$PATH"
export LDFLAGS="-L/usr/local/opt/llvm/lib"
export CPPFLAGS="-I/usr/local/opt/llvm/include"
Setting PATH is straight forward. I however, didn't need to set LDFLAGS or CPPFLAGS. Further, no joy with this additional caveat, "To use the bundled libc++ please add the following LDFLAGS":
export LDFLAGS="-L/usr/local/opt/llvm/lib -Wl,-rpath,/usr/local/opt/llvm/lib"
Anyway, moving on... To demonstrate that all's good, a C++ foo program that incorporates <filesystem>; a library not in High Sierra:
#include <iostream>
// C++17: Modern C++ compiler has std filesystem
#include <filesystem>
namespace fs = std::filesystem;
typedef std::filesystem::path my_path;
using namespace std;
int main ()
{
fs::path path{"/tmp"};
path /= "foo.txt";
ofstream ofs(path);
ofs << "Hello World." << endl;
ofs.close();
return 0;
}
Clearly, a nonsensical program, But to compile:
unset CPPFLAGS
unset LDFLAGS
clang++ -std=c++17 -L/usr/local/opt/llvm/lib foo.cpp -o foo
Again, showing That I didn't need CPPFLAGS and LDFLAGS. And so, The executable links to the correct libc++ library:
MacIntel:c++fs mjo$ otool -L foo
foo:
/usr/local/opt/llvm/lib/libc++.1.dylib (compatibility version 1.0.0, current version 1.0.0)
/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1252.50.4)
Enjoy.
These are the step I follow to install doxygen 1.8.20:
apt-get install graphviz
apt-get install bison
apt-get install flex
wget http://ftp.gnu.org/pub/gnu/libiconv/libiconv-1.16.tar.gz
tar -xvzf libiconv-1.16.tar.gz
cd libiconv-1.16
./configure --prefix=/usr/local/libiconv
make
make install
wget http://doxygen.nl/files/doxygen-1.8.20.src.tar.gz
gunzip doxygen-1.8.20.src.tar.gz
tar -xf doxygen-1.8.20.src.tar
cd doxygen-1.8.20
mkdir build
cd build
cmake -G "Unix Makefiles" -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=/usr -Duse_libclang=ON ..
At this point I get the following output:
CMake Error at CMakeLists.txt:51 (find_package):
Could not find a package configuration file provided by "LLVM" with any of
the following names:
LLVMConfig.cmake
llvm-config.cmake
Add the installation prefix of "LLVM" to CMAKE_PREFIX_PATH or set
"LLVM_DIR" to a directory containing one of the above files. If "LLVM"
provides a separate development package or SDK, be sure it has been
installed.
-- Configuring incomplete, errors occurred!
See also "/home/doxygen-1.8.20/build/CMakeFiles/CMakeOutput.log".
Now I get LLVM package:
apt-get install llvm
cmake -G "Unix Makefiles" -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=/usr -Duse_libclang=ON ..
At this point I get the following output:
CMake Error at CMakeLists.txt:52 (find_package):
Could not find a package configuration file provided by "Clang" with any of
the following names:
ClangConfig.cmake
clang-config.cmake
Add the installation prefix of "Clang" to CMAKE_PREFIX_PATH or set
"Clang_DIR" to a directory containing one of the above files. If "Clang"
provides a separate development package or SDK, be sure it has been
installed.
-- Configuring incomplete, errors occurred!
Get clang package:
apt-get install clang
Get the same error:
CMake Error at CMakeLists.txt:52 (find_package):
Could not find a package configuration file provided by "Clang" with any of
the following names:
ClangConfig.cmake
clang-config.cmake
Add the installation prefix of "Clang" to CMAKE_PREFIX_PATH or set
"Clang_DIR" to a directory containing one of the above files. If "Clang"
provides a separate development package or SDK, be sure it has been
installed.
-- Configuring incomplete, errors occurred!
See also "/home/doxygen-1.8.20/build/CMakeFiles/CMakeOutput.log".
Now What?
This was found to be a problem with the llvm and clang that get installed with apt-get install llvm and apt-get install clang. This installs version 6 of both.
Instead of these commands, do the following:
apt install llvm-10 clang-10 libclang-10-dev
Then running
cmake -G "Unix Makefiles" -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=/usr -Duse_libclang=ON ..
will produce successful output:
-- Found PythonInterp: /usr/bin/python (found version "2.7.17")
-- Found FLEX: /usr/bin/flex (found version "2.6.4")
-- Found BISON: /usr/bin/bison (found version "3.0.4")
-- Looking for pthread.h
-- Looking for pthread.h - found
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD - Failed
-- Looking for pthread_create in pthreads
-- Looking for pthread_create in pthreads - not found
-- Looking for pthread_create in pthread
-- Looking for pthread_create in pthread - found
-- Found Threads: TRUE
-- Looking for iconv_open
-- Looking for iconv_open - found
-- Performing Test ICONV_COMPILES
-- Performing Test ICONV_COMPILES - Success
-- Found Iconv: In glibc
-- One (and only one) of the ICONV_ACCEPTS_... tests must pass
-- Performing Test ICONV_ACCEPTS_NONCONST_INPUT
-- Performing Test ICONV_ACCEPTS_NONCONST_INPUT - Success
-- Performing Test ICONV_ACCEPTS_CONST_INPUT
-- Performing Test ICONV_ACCEPTS_CONST_INPUT - Failed
-- The javacc executable not found, using existing files
-- Configuring done
-- Generating done
-- Build files have been written to: /home/libiconv-1.16/doxygen-1.8.20/build
and proceed with make and make install
I am trying to build the OpenCV samples which come with the source package and I get the following:
CMake Error at CMakeLists.txt:10 (ocv_check_dependencies):
Unknown CMake command "ocv_check_dependencies".
I did install OpenCV using
cmake .
make
sudo make install
and I got a tutorial snippet working (thus I suppose it is installed correctly as a library). However, compiling the samples does not work.
I guess I have to somehow configure CMake to have âocv_check_dependenciesâ - but how? I am lost!
Actually for OpenCV 2.4.4 beta the root CMakeList.txt file says:
OCV_OPTION(BUILD_EXAMPLES "Build all examples"
-DBUILD_EXAMPLES=ON worked just fine for me.
I got it.
In order to build the samples one has to change the default configuration for cmake by providing it via -D. What I did wrong was that I tried to execute cmake from within the samples directory.
The proper way to build the samples is invoking cmake like so (from within the root directory of the unpacked archive):
cmake -DBUILD_SAMPLES .
which will turn samples ON. One can proceed using make, make install than. The samples can be found in bin after building.
See also FAQ
How to compile OpenCV sample code ?
# For OpenCV 3
cd /path/to/opencv/samples/cpp/
#Compile
g++ -ggdb `pkg-config --cflags --libs opencv` facedetect.cpp -o facedetect
#run
./facedetect
Works for me.
googled from this link
mydragonisland's build instructions almost worked for me; with a minor reordering and including accents:
g++ facedetect.cpp -o facedetect `pkg-config --libs opencv`
The macro 'ocv_check_dependencies' is defined in: your_path_to/opencv/cmake/OpenCVModule.cmake
# ensures that all passed modules are available
# sets OCV_DEPENDENCIES_FOUND variable to TRUE/FALSE
macro(ocv_check_dependencies)
set(OCV_DEPENDENCIES_FOUND TRUE)
foreach(d ${ARGN})
if(d MATCHES "^opencv_[^ ]+$" AND NOT HAVE_${d})
set(OCV_DEPENDENCIES_FOUND FALSE)
break()
endif()
endforeach()
endmacro()
The top level CMakeLists.txt contains 'include' commands for files from opencv/cmake/ . Which is why the macro is available when you compile by calling cmake from the root of the opencv sources.
Reason
error message context:
CMake Error at CMakeLists.txt:10 (ocv_check_dependencies):
Unknown CMake command "ocv_check_dependencies".
This error message happens because cmake can't find the definition of ocv_check_dependencies
That's why the console said Unknown CMake command
Solution
If cmake cannot find where ocv_check_dependencies is defined
Just like #Nick Hockings Said:
ocv_check_dependencies is a macro defined in Your/OpenCV/path/OpenCVModule.cmake
macro(ocv_check_dependencies)
set(OCV_DEPENDENCIES_FOUND TRUE)
foreach(d ${ARGN})
if(d MATCHES "^opencv_[^ ]+$" AND NOT HAVE_${d})
set(OCV_DEPENDENCIES_FOUND FALSE)
break()
endif()
endforeach()
endmacro()
The fastest way is to copy this snippet above to your CMakeList.txt file right above where ocv_check_dependencies is
Therefore, cmake can finally understand what it is
That should do the trick, i hope no one else will bother with this question in the future
I got similar errors. My approach is as following:
1) cd xxx/samples 2) mkdir build 3) cd build 4) cmake .. 5) make
Now it works. We could not build individual project under their source files.
Following steps works for me.
Export toolchain path.
cd opencv-3.3.0/samples
cross_cmake &&
cross_make
cd opencv-3.3.0/samples/cpp/
When I try to build Assimp by running build_ios.sh, it tells me:
CMake Error: your C compiler: "/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/llvm-gcc" was not found. Please set CMAKE_C_COMPILER to a valid compiler path or name.
CMake Error: your CXX compiler: "/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/llvm-g++" was not found. Please set CMAKE_CXX_COMPILER to a valid compiler path or name.
What I need the path to be is:
/Applications/XCode.app/Contents/Developer/Platforms/...
I've tried changing DEVROOT in build_ios.sh and IPHONE_xxxx_TOOLCHAIN.cmake, because that's what CMAKE_C_COMPILER etc seem to get generated from, but it still gives me the same errors.
Option 1:
You can set CMake variables at command line like this:
cmake -D CMAKE_C_COMPILER="/path/to/your/c/compiler/executable" -D CMAKE_CXX_COMPILER "/path/to/your/cpp/compiler/executable" /path/to/directory/containing/CMakeLists.txt
See this to learn how to create a CMake cache entry.
Option 2:
In your shell script build_ios.sh you can set environment variables CC and CXX to point to your C and C++ compiler executable respectively, example:
export CC=/path/to/your/c/compiler/executable
export CXX=/path/to/your/cpp/compiler/executable
cmake /path/to/directory/containing/CMakeLists.txt
Option 3:
Edit the CMakeLists.txt file of "Assimp": Add these lines at the top (must be added before you use project() or enable_language() command)
set(CMAKE_C_COMPILER "/path/to/your/c/compiler/executable")
set(CMAKE_CXX_COMPILER "/path/to/your/cpp/compiler/executable")
See this to learn how to use set command in CMake. Also this is a useful resource for understanding use of some of the common CMake variables.
Here is the relevant entry from the official FAQ: https://gitlab.kitware.com/cmake/community/wikis/FAQ#how-do-i-use-a-different-compiler
The cc and cxx is located inside /Applications/Xcode.app. This should find the right paths
export CXX=`xcrun -find c++`
export CC=`xcrun -find cc`
SOLUTIONS
Sometimes the project is created before installing g++. So install g++ first and then recreate your project. This worked for me.
Paste the following line in CMakeCache.txt:
CMAKE_CXX_COMPILER:FILEPATH=/usr/bin/c++
Note the path to g++ depends on OS. I have used my fedora path obtained using which g++
I'm trying real hard to install vowpal wobbit and it fails when i run the make file, throwing:
cd library; make; cd ..
g++ -g -o ezexample temp2.cc -L ../vowpalwabbit -l vw -l allreduce -l boost_program_options -l z -l pthread
ld: library not found for -lboost_program_options collect2: ld returned 1 exit status make[1]: *** [ezexample] Error 1'
I then added the links to the boost library here by specifying -L/usr/local/lib
Now I get the following error:
g++ -g -o ezexample temp2.cc -L/usr/local/lib ../vowpalwabbit -l vw -l allreduce -l boost_program_options -l z -l pthread
ld: library not found for -lvw
collect2: ld returned 1 exit status
make: *** [ezexample] Error 1
I happened to get everything working on OS X 10.7 as follows:
Make sure you have a working Boost installation. As indicated on the Getting started page, usually we only need header files, but some Boost libraries must be built separately, including the program_options library which is used to process options from command line or config file. Go into your boost folder, and then at your shell prompt:
$ ./bootstrap.sh
$ ./bjam
This will compile and build everything. You should now have a bin.v2/ directory in your boost directory, with all built libraries for your system (static and threaded libs).
$ ls bin.v2/libs/
date_time iostreams python serialization test
filesystem math random signals thread
graph program_options regex system wave
More importantly, extra Boost libraries are made available in the stage/lib/ directory. For me, these are Mach-O 64-bit dynamically linked shared library x86_64.
The include path should be your_install_dir/boost_x_xx_x, where boost_x_xx_x is the basename of your working Boost. (I personally have boost_1_46_1 in /usr/local/share/ and I symlinked it to /usr/local/share/boost to avoid having to remember version number.) The library path (for linking) should read your_install_dir/boost_x_xx_x/stage/lib. However, it might be best to symlink or copy (which is what I did) everything in usual place, i.e. /usr/local/include/boost for header files, and /usr/local/lib for libraries.
Edit the Makefile from the vowpal_wabbit directory, and change the include/library paths to reflect your current installation. The Makefile should look like this (first 12 lines):
COMPILER = g++
UNAME := $(shell uname)
ifeq ($(UNAME), FreeBSD)
LIBS = -l boost_program_options -l pthread -l z -l compat
BOOST_INCLUDE = /usr/local/include
BOOST_LIBRARY = /usr/local/lib
else
LIBS = -l boost_program_options -l pthread -l z
BOOST_INCLUDE = /usr/local/share/boost # change path to reflect yours
BOOST_LIBRARY = /usr/local/share/boost/stage/lib # idem
endif
Then, you are ready to compile vowpal_wabbit (make clean in case you already compiled it):
$ make
$ ./vw --version
6.1
$ make test
You can also install vowpal wabbit on OS X using brew:
brew install vowpal-wabbit
Or you can just install boost, and then install vw from the github repo.
brew install boost
For installation on CentOS 7 (6.5 perl version is too old for latest vw source code), I've found the instructions at http://wkoplitz.blogspot.be/2012/12/vowpal-wabbit-on-centos.html to work fine:
yum install zlib-devel boost-devel
yum groupinstall "Development Tools"
git clone git://github.com/JohnLangford/vowpal_wabbit.git
cd vowpal_wabbit
./autogen.sh
make
make test
Good news:
As of the latest release VowpalWabbit version 9.1.0, vw no longer relies on Boost program_options
From the release highlights:
Removal of Boost Program Options dependency
For a long time we have depended on Boost Program Options
for command line options parsing. In this release, we have > replaced this dependency with our own implementation of
command line parsing. Apart from one place where we depend > on Boost Math in standalone mode, this means that VW core
and the command line tool are free of Boost dependencies
hopefully making the code a bit easier to build and package.
Vowpal Wabbit 9.1.0 release notes