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c++linuxeclipsecross-compilingcrypto++

Compiling Crypto++ for armhf for cross compiling

I want to cross compile the library crypto++ for deployment on a beaglebone running Debian. My host PC runs Ubuntu 14.04 LTS in a 64-bit configuration.

I face the following problem when I invoke the make command from eclipse

arm-linux-gnueabihf-g++-4.8 -L/usr/include/cryptopp -o "GCMwithAES"  ./main.o   -lcryptopp
/usr/lib/../lib/libcryptopp.so: file not recognized: File format not recognized

My guess is that since the compiler is configured for armhf, it cannot recognize the library that was compiled for amd64.

I have successfully cross compiled and run standard (ie no external libraries) programs from my host PC to my target device.

Solutions that I have tried

  • Used libcrypto++ packages with the architecture specified as armhf as done in multiarch. The armhf libraries get installed ( as per apt) but I am unable to include and link my code with them.
  • Manually try to compile the library as per the instruction given on this wiki. However, I always run into errors whenever I try to compile the library.

How do I install the libcryptopp libraries of the armhf architecture on my x64 based PC so I can cross compile? or is there any other way to resolve this issue.

Edit

As suggested in the answer below I tried out the method suggested. I slightly modified the script setenv-embed.sh since I had gcc-4.8 instead of gcc-4.7. The results of running the script are

CPP: /usr/bin/arm-linux-gnueabihf-cpp 
CXX: /usr/bin/arm-linux-gnueabihf-g++
AR: /usr/bin/arm-linux-gnueabihf-ar
LD: /usr/bin/arm-linux-gnueabihf-ld
RANLIB: /usr/bin/arm-linux-gnueabihf-gcc-ranlib-4.8

ARM_EMBEDDED_TOOLCHAIN: /usr/bin
ARM_EMBEDDED_CXX_HEADERS: /usr/arm-linux-gnueabihf/include/c++/4.8.2
ARM_EMBEDDED_FLAGS: -march=armv7-a mfloat-abi=hard -mfpu=neon -I/usr/arm-linux-gnueabihf/include/c++/4.8.2 -I/usr/arm-linux-gnueabihf/include/c++/4.8.2/arm-linux-gnueabihf 
ARM_EMBEDDED_SYSROOT: /usr/arm-linux-gnueabihf

I build the library using the make command and run into the following error

/usr/lib/gcc-cross/arm-linux-gnueabihf/4.8/../../../../arm-linux-gnueabihf/bin/‌​ld: cannot find /usr/arm-linux-gnueabihf/lib/libc.so.6 inside /usr/arm-linux-gnueabihf
/usr/lib/gcc-cross/arm-linux-gnueabihf/4.8/../../../../arm-linux-gnueabihf/bin/‌​ld: cannot find /usr/arm-linux-gnueabihf/lib/libc_nonshared.a inside /usr/arm-linux-gnueabihf        
/usr/lib/gcc-cross/arm-linux-gnueabihf/4.8/../../../../arm-linux-gnueabihf/bin/‌​ld: cannot find /usr/arm-linux-gnueabihf/lib/ld-linux-armhf.so.3 inside /usr/arm-linux-gnueabihf

But when I open the location /usr/arm-linux-gnueabihf/lib I can find all the three error files mentioned above ie libc.so.6, libc_nonshared.a and ld-linux-armhf.so.3

As per the suggestions of @jww, I'm shifting this to a new question since I'm having trouble linking. My results here are left for completeness.

Solution

  • How do I install the libcryptopp libraries of the armhf architecture on my x64 based PC so I can cross compile? or is there any other way to resolve this issue.

    Checkout ARM Embedded (Command Line) on the Crypto++ wiki.

    Note: that wiki page is a bit dated. You can now use GNUmakefile-cross. I have not updated the page to reflect recent changes like GNUmakefile-cross.

    GNUmakefile-cross is a special purpose built for cross-compiling on Android, iOS, Windows Phone, ARM Embedded, and bare metal (I doubt anyone would do the later, but I tested it as a platform). You will still need to run the setenv-embedded.sh script.

    To fetch the latest sources from GitHub:

    git clone https://github.com/weidai11/cryptopp.git cryptopp-armhf

    The GitHub sources are quite active at the moment. We are preparing for a Crypto++ 5.6.3 release. 5.6.3 will include GNUmakefile-cross.

    The complete instructions will look something like (assuming you have the tools installed):

    git clone https://github.com/weidai11/cryptopp.git cryptopp-armhf
cd cryptopp-armhf

# Note the leading dot!!!
. ./setenv-embedded.sh
# The command above must execute successfully
# It cannot display a message like "**CXX is not valid**"

# Build it
make -f GNUmakefile-cross static dynamic cryptest.exe

# Check it
$ find . -name cryptest.exe
./cryptest.exe
$ /usr/bin/arm-linux-gnueabi-readelf -h ./cryptest.exe | grep -i 'class\|machine' 
  Class:                             ELF32
  Machine:

    Because the GitHub sources are quite active at the moment, I've already added all the other files from Crypto++-Mobile.zip and Setenv-embedded.sh.zip to the official Crypto++ sources. You only need to get setenv-embedded.sh out of the Setenv-embedded.sh.zip.