std namespace errors while compiling using cmake

[ashishmagar600]

I am building a cross-compilation platform using OpenCV 3.4.4, darknet (and its dependencies) and DarkHelp.

DarkHelp dependencies such as magic, tclap etc have been cross-compiled successfully along with OpenCV and darknet. I have tested it on my RPi, the darknet libs and exe works.

When I try to compile Darkhelp,

cmake -DOpenCV_DIR="${RPI_SYSROOT}/usr/local/lib" -DCMAKE_PREFIX_PATH="${RPI_SYSROOT}/usr/local" ..

-- The C compiler identification is GNU 7.5.0
-- The CXX compiler identification is GNU 7.5.0
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: /usr/bin/cc - skipped
-- Detecting C compile features
-- Detecting C compile features - done
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /usr/bin/c++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
Building ver: 1.4.18-1
-- 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  
-- Found OpenCV: /home/develop/RPi-sysroot/usr/local (found version "3.4.4") 
-- Configuring done
-- Generating done
-- Build files have been written to: 

make -j4

[ 11%] Building CXX object src-lib/CMakeFiles/dh.dir/DarkHelpConfig.cpp.o
In file included from /usr/include/c++/7/ext/string_conversions.h:41:0,
                 from /usr/include/c++/7/bits/basic_string.h:6361,
                 from /usr/include/c++/7/string:52,
                 from /usr/include/c++/7/stdexcept:39,
                 from /usr/include/c++/7/array:39,
                 from /usr/include/c++/7/tuple:39,
                 from /usr/include/c++/7/bits/stl_map.h:63,
                 from /usr/include/c++/7/map:61,
                 from /home/develop/test_darknet/DarkHelp/src-lib/DarkHelp.hpp:9,
                 from /home/develop/test_darknet/DarkHelp/src-lib/DarkHelpConfig.cpp:6:
/usr/include/c++/7/cstdlib:144:11: error: '::calloc' has not been declared
   using ::calloc;
           ^~~~~~
/usr/include/c++/7/cstdlib:147:11: error: '::free' has not been declared
   using ::free;
           ^~~~
/usr/include/c++/7/cstdlib:151:11: error: '::malloc' has not been declared
   using ::malloc;
           ^~~~~~

This is a short part of the error. All the calls to std:: are reported.

While searching for a solution, I found this post

It seems some include<> are done within the namespace{} as I came across multiple forum posts. Let me know if any more information is required to find a solution.

[stephanecharette]

Sorry, I have no idea. I do build regularly on my RPI without problem. Let me know if you find the cause.

[ashishmagar600]

Can you share the method to compile DarkHelp on RPi? Thanks

…

On Fri, 10 Jun, 2022, 20:17 Stéphane Charette, ***@***.***> wrote: Sorry, I have no idea. I do build regularly on my RPI without problem. Let me know if you find the cause. — Reply to this email directly, view it on GitHub <#27 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AHBKSHVYNTUIVBBIUH7UGMDVONIRZANCNFSM5YN5B3RA> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[stephanecharette]

Yes, I have it documented here: https://github.com/stephanecharette/DarkHelp#building-darknet-linux

All of my RPI devices run Ubuntu for RPI: https://ubuntu.com/download/raspberry-pi

This makes it extremely easy to build anything. You simply follow the normal Linux/Ubuntu instructions.

[ashishmagar600]

I was looking for a way to cross-compile DarkHelp, but this is also helpful.

Thanks