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Topic: SDK doesn´t cross-compile :-(

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Post #1
iwakura
10 Dec 2007, 00:02

Hi all,

I'm having trouble with the SDK; I'd really appreciate it if someone could give me a hand here :-((((

I have a wl-hdd running whiterussian (latest 0.9), and I'm trying to cross-compile a small application on my i686 linux PC, using the OpenWRT-SDK (i took the one from http://downloads.openwrt.org/whiterussi … 1.tar.bz2).
But for whatever reason the .ipk that is generated still seems to contain code for the host (i.e. i686) machine, not for the WL-HDD (mipsel); on the WL-HDD the binary generates an error (/bin/helloworld: 1 Syntax error: "(" unexpected). The same binary, on the i686-PC executes...

I followed the instructions for using the SDK found in http://people.bu.edu/ebishop/openwrt-programming.html (The SDK is installed in "/home/ubuntu/SDK/")
* created a directory in packages (/home/ubuntu/SDK/package/helloworld)
* the helloworld directory contains the Makefile (/home/ubuntu/SDK/package/helloworld/Makefile)
    and a src directory containing the application sourcecode (/home/ubuntu/SDK/package/helloworld/src/helloworld.c)
    (i don't download the sourcecode, but copy it from src to $(PKG_BUILD_DIR) in Build/Prepare)
* when i execute make in /home/ubuntu/SDK/, everything seems to work, and i find helloworld_1_mipsel.ipk in
   /home/ubuntu/SDK/bin/packages. But this ipk doesn't work on the wl-hdd. I transfered it from the PC to the WL-HDD using ftp,
   installed it (ipkg install helloworld_1_mipsel.ipk), but binary just generates the syntax error mentioned above. the same binary
   (bin/helloworld), transfered back to the PC, executed perfectly. that's why I think that the SDK compiled the package for the i686-host
    machine, not for the mipsel. but I have no idea why.
Below I'll post the sourcecode, the makefile and the V=99 output of make; I hope someone can help me here :-(

I also noticed one funny thing, don´t know if it matters: the Makefile in the SDK directory (home/ubuntu/SDK/Makefile) contains a line "RELEASE=Kamikaze", although I downloaded the SDK from the whiterussian directory.

Thanks a lot!!
Chris



==========The sourcecode: /home/ubuntu/SDK/package/helloworld/src/helloworld.c================
#include <stdio.h>

int main(void)
{
printf("Hell! Oh world, why don't my code compile ??\n");
return 0;
}
=================================================


========/home/ubuntu/SDK/package/helloworld/Makefile===========
include $(TOPDIR)/rules.mk

PKG_NAME:=helloworld
PKG_RELEASE:=1

PKG_BUILD_DIR := $(BUILD_DIR)/$(PKG_NAME)

include $(INCLUDE_DIR)/package.mk

define Package/helloworld
    SECTION:=utils
     CATEGORY:=Utilities
    TITLE:=Helloworld
endef

# copy the source files to the build directory (this is NOT the default)
# The default uses PKG_SOURCE_URL and the PKG_SOURCE to download the source from the web.
define Build/Prepare
    mkdir -p $(PKG_BUILD_DIR)
    $(CP) ./src/* $(PKG_BUILD_DIR)/
endef


define Package/helloworld/install
    $(INSTALL_DIR) $(1)/bin
    $(INSTALL_BIN) $(PKG_BUILD_DIR)/helloworld $(1)/bin/
endef

$(eval $(call BuildPackage,helloworld))
=================================================


===============Output of /home/ubuntu/SDK/make V=99  ============
make package/compile
make[1]: Entering directory `/home/ubuntu/OpenWrt-SDK-Linux-i686-1'
make -C package compile SDK=1
make[2]: Entering directory `/home/ubuntu/OpenWrt-SDK-Linux-i686-1/package'
make -j1 compile-targets
make[3]: Entering directory `/home/ubuntu/OpenWrt-SDK-Linux-i686-1/package'
mkdir -p /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/stamp
mkdir -p /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/root
make -C helloworld compile
Rebuilding /home/ubuntu/OpenWrt-SDK-Linux-i686-1/bin/packages/helloworld_1_mipsel.ipk
make[4]: Entering directory `/home/ubuntu/OpenWrt-SDK-Linux-i686-1/package/helloworld'
mkdir -p /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld
cp -fpR ./src/* /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/
touch /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/.prepared
(cd /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/; if [ -x configure ]; then AR=mipsel-linux-uclibc-ar AS="mipsel-linux-uclibc-gcc -c -Os -pipe -mips32 -mtune=mips32 -funit-at-a-time" LD=mipsel-linux-uclibc-ld NM=mipsel-linux-uclibc-nm CC="mipsel-linux-uclibc-gcc" GCC="mipsel-linux-uclibc-gcc" CXX=mipsel-linux-uclibc-g++ RANLIB=mipsel-linux-uclibc-ranlib STRIP=mipsel-linux-uclibc-strip OBJCOPY=mipsel-linux-uclibc-objcopy CFLAGS="-Os -pipe -mips32 -mtune=mips32 -funit-at-a-time" CXXFLAGS="-Os -pipe -mips32 -mtune=mips32 -funit-at-a-time" CPPFLAGS="-I/home/ubuntu/OpenWrt-SDK-Linux-i686-1/staging_dir_mipsel/usr/include -I/home/ubuntu/OpenWrt-SDK-Linux-i686-1/staging_dir_mipsel/include" LDFLAGS="-L/home/ubuntu/OpenWrt-SDK-Linux-i686-1/staging_dir_mipsel/usr/lib -L/home/ubuntu/OpenWrt-SDK-Linux-i686-1/staging_dir_mipsel/lib" PKG_CONFIG_PATH="/home/ubuntu/OpenWrt-SDK-Linux-i686-1/staging_dir_mipsel/usr/lib/pkgconfig" PKG_CONFIG_LIBDIR="/home/ubuntu/OpenWrt-SDK-Linux-i686-1/staging_dir_mipsel/usr/lib/pkgconfig"  ./configure --target=mipsel-linux --host=mipsel-linux --build=i486-linux-gnu --program-prefix="" --program-suffix="" --prefix=/usr --exec-prefix=/usr --bindir=/usr/bin --sbindir=/usr/sbin --libexecdir=/usr/lib --sysconfdir=/etc --datadir=/usr/share --localstatedir=/var --mandir=/usr/man --infodir=/usr/info --disable-nls ; fi; )
touch /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/.configured
CFLAGS="-Os -pipe -mips32 -mtune=mips32 -funit-at-a-time -I/home/ubuntu/OpenWrt-SDK-Linux-i686-1/staging_dir_mipsel/usr/include -I/home/ubuntu/OpenWrt-SDK-Linux-i686-1/staging_dir_mipsel/include " LDFLAGS="-L/home/ubuntu/OpenWrt-SDK-Linux-i686-1/staging_dir_mipsel/usr/lib -L/home/ubuntu/OpenWrt-SDK-Linux-i686-1/staging_dir_mipsel/lib " make -C /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld AR=mipsel-linux-uclibc-ar AS="mipsel-linux-uclibc-gcc -c -Os -pipe -mips32 -mtune=mips32 -funit-at-a-time" LD=mipsel-linux-uclibc-ld NM=mipsel-linux-uclibc-nm CC="mipsel-linux-uclibc-gcc" GCC="mipsel-linux-uclibc-gcc" CXX=mipsel-linux-uclibc-g++ RANLIB=mipsel-linux-uclibc-ranlib STRIP=mipsel-linux-uclibc-strip OBJCOPY=mipsel-linux-uclibc-objcopy CROSS="mipsel-linux-uclibc-" CXXFLAGS="-Os -pipe -mips32 -mtune=mips32 -funit-at-a-time -I/home/ubuntu/OpenWrt-SDK-Linux-i686-1/staging_dir_mipsel/usr/include -I/home/ubuntu/OpenWrt-SDK-Linux-i686-1/staging_dir_mipsel/include " ARCH="mipsel" ;
make[5]: Entering directory `/home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld'
make[5]: `helloworld' is up to date.
make[5]: Leaving directory `/home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld'
touch /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/.built
mkdir -p /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld/CONTROL
echo "Package: helloworld" > /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld/CONTROL/control
echo "Version: 1" >> /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld/CONTROL/control
( DEPENDS=''; for depend in ; do DEPENDS=${DEPENDS:+$DEPENDS, }${depend##+}; done; echo "Depends: $DEPENDS" >> /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld/CONTROL/control; )
echo "Source: package/helloworld" >> /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld/CONTROL/control
echo "Section: utils" >> /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld/CONTROL/control
echo "Priority: optional" >> /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld/CONTROL/control
echo "Maintainer: OpenWrt Developers Team <openwrt-devel@openwrt.org>" >> /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld/CONTROL/control
echo "Architecture: mipsel" >> /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld/CONTROL/control
echo "Description: Helloworld -- prints a snarky message\\ If you can't figure out what this program does, \ you're probably brain-dead and need immediate \ medical attention." | sed -e 's,\\,\n,g' | sed -e 's,^[[:space:]]*$, .,g' >> /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld/CONTROL/control
chmod 644 /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld/CONTROL/control
(cd /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld/CONTROL; var2file "V_Package_helloworld_conffiles" conffiles; var2file "V_Package_helloworld_preinst" preinst; var2file "V_Package_helloworld_postinst" postinst; var2file "V_Package_helloworld_prerm" prerm; var2file "V_Package_helloworld_postrm" postrm; )
install -d -m0755 /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld/bin
install -m0755 /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/helloworld /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld/bin/
mkdir -p /home/ubuntu/OpenWrt-SDK-Linux-i686-1/bin/packages
find /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld -name CVS | xargs rm -rf
find /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld -name .svn | xargs rm -rf
find /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld -name '.#*' | xargs rm -f
STRIP="/home/ubuntu/OpenWrt-SDK-Linux-i686-1/staging_dir_mipsel/bin/sstrip" STRIP_KMOD="mipsel-linux-uclibc-strip --strip-unneeded --remove-section=.comment" /home/ubuntu/OpenWrt-SDK-Linux-i686-1/scripts/rstrip.sh /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld
rstrip.sh: /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld/bin/helloworld:executable
ipkg-build -c -o 0 -g 0 /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld /home/ubuntu/OpenWrt-SDK-Linux-i686-1/bin/packages
Packaged contents of /home/ubuntu/OpenWrt-SDK-Linux-i686-1/build_mipsel/helloworld/ipkg/helloworld into /home/ubuntu/OpenWrt-SDK-Linux-i686-1/bin/packages/helloworld_1_mipsel.ipk
make[4]: Leaving directory `/home/ubuntu/OpenWrt-SDK-Linux-i686-1/package/helloworld'
make[3]: Leaving directory `/home/ubuntu/OpenWrt-SDK-Linux-i686-1/package'
make[2]: Leaving directory `/home/ubuntu/OpenWrt-SDK-Linux-i686-1/package'
make[1]: Leaving directory `/home/ubuntu/OpenWrt-SDK-Linux-i686-1'
( \
        cd package; \
        find . -maxdepth 2 -name Config.in | \
            sed -e 's,/Config.in,,g' | \
            xargs -r -n1 make compile -C; \
    )
=================================================

Post #2
ebishop
27 Jan 2008, 17:56

Hi, I wrote the tutorial you reference.  I wish you'd emailed me directly with your problem or posted your problem to the thread in the howto forum where I initially posted the tutorial, which I check frequently.  As it is I apologize for only getting you an answer over two months later.

The problem is that after you tested the program on your own system you didn't get rid of the object files by running "make clean."  If you look within the directory you copied to [SDK directory]/package/helloworld/src you'll find a bunch of ,o files that were generated by the compiler on your linux box.  I apologize, I originally showed the running of the "make clean" command in one of the black boxes that show shell output, but never explicitly said in the text that this was necessary and why. I have since fixed the problem with the tutorial (another user commented on this issue more recently), stressing the importance of running make clean after testing the program locally.

I hope this helps (2+ months late).

The discussion might have continued from here.