Cannot find /lib/libc.so.6

Question

I'm cross-compiling an application, but linking blows up with an error that it

"cannot find /lib/libc.so.6".

The libc.so.6 that it should be using is the one that sits at /home/work/worldcom/filesys/lib/libc.so.6. What have I got wrong here?

linking libobj.so
arm-none-linux-gnueabi-g++ obj1.o obj2.o obj2.o  -o libobj.so -L/home/work/worldcom/filesys/usr -Wl,-O1 -Wl,-z,defs -Wl,--enable-new-dtags -Wl,--sort-common -Wl,--as-needed -Wl,--hash-style=both -L/home/work/worldcom/filesys -L/home/work/worldcom/filesys/lib -L/home/work/worldcom/filesys/usr/lib -lcurl -shared
/home/lishevita/armv5tel/arm-2009q3/bin/../lib/gcc/arm-none-linux-gnueabi/4.4.1/../../../../arm-none-linux-gnueabi/bin/ld: skipping incompatible /lib/libc.so.6 when searching for /lib/libc.so.6
/home/lishevita/armv5tel/arm-2009q3/bin/../lib/gcc/arm-none-linux-gnueabi/4.4.1/../../../../arm-none-linux-gnueabi/bin/ld: cannot find /lib/libc.so.6
collect2: ld returned 1 exit status<br />
make: *** [libobj.so] Error 1<br />

My makefile is handwritten (i.e. not generated by Autotools). In order to avoid a blanket "your Makefile is broken" here are some details from the makefile that might help clarify.

CROSS_COMPILE = arm-none-linux-gnueabi-  
SYSROOT = /home/work/worldcom/filesys/  
DESTDIR = /home/work/worldcom/filesys/  

RELEASE_CXXFLAGS = -Os  
DEBUG_CXXFLAGS = -O0 -gstabs  
PKGCONFIG=`env ROOT=/home/work/worldcom/filesys cross-pkg-config glib-2.0 libcurl --cflags`  

CC = $(CROSS_COMPILE)gcc  
CXX = $(CROSS_COMPILE)g++  
LD = $(CROSS_COMPILE)ld  
AR = $(CROSS_COMPILE)ar  

LDFLAGS = -Wl,-O1 -Wl,-z,defs -Wl,--enable-new-dtags -Wl,--sort-common -Wl,--as-needed -Wl,--hash-style=both -L$(SYSROOT) -L$(SYSROOT)lib -L$(SYSROOT)usr -L$(SYSROOT)usr/lib -lcurl  

libobj.so: $(LIBOBJ_OBJS)  
        @echo linking $@  
        $(CXX) $^ -o $@ $(LDFLAGS) -shared $(PKG_LIBS) 

Of course there is also a definition and target for the LIBOBJ_OBJS but those are irrelevant to the problem.

Answer 1

You didn't indicate what gcc version you are using, but if it is a recent enough one (4.0.0 and above me thinks) you should try adding the --sysroot flag to g++/ld. Point it to $SYSROOT as defined in your Makefile. For example:

--sysroot=$(SYSROOT)

Assuming recent enough gcc version, it will work.

Answer 2

I just went through the same issue; adding --sysroot=/rootfs/prefix helped me get closer to the real issue. I got it fixed by installing package libstdc++-dev in target.