Re: gcj static crosscompiling raises issues with boehm-gc

[David Daney <ddaney@caviumnetworks.com>]

On 10/06/2010 07:25 AM, Andrew Haley wrote:
> On 10/06/2010 09:43 AM, Andreas Frisch wrote:
>> hi gcj experts,
>>
>> i've spent some time already trying to statically cross compile a java source
>> for an embedded mipsel architecture. i'm using openembedded and gcc-4.4.4 with
>> the latest java part imported from master
>>
>> in the makefile, i am using the command
>>
>> $(CROSS_COMPILE)gcj $(JFLAGS) $(SOURCES) \
>> 		-static-libgcj \
>> 		-fjni \
>> 		-g \
>> 		-o dumphd-mipsel-static \
>> 		 --main=dumphd.core.DumpHD \
>> 		-nostdlib \
>> 		-L/dream/oe1.6/dm8000/build/tmp/staging/mipsel-oe-linux/usr/lib \
>> 		-L/dream/projects/bluray/aacskeys-0.4.0c-mipsel/lib/linux/ \
>> 		-Wl,-rpath-link,/dream/oe1.6/dm8000/build/tmp/staging/mipsel-oe-
>> linux/usr/lib \
>> 		-Wl,-rpath-link,/dream/projects/bluray/aacskeys-0.4.0c-
>> mipsel/lib/linux/ -laacskeys \
>> 		-shared-libgcc -Wl,-non_shared -lgcj -Wl,-call_shared -lstdc++ -
>> Wl,--as-needed -lgcc_s -lpthread -lc -lm -ldl -lrt -Wl,--no-as-needed -Wl,-O1
>>
>> this may contain a lot of redundancies or look silly in many ways but for
>> right now i just aggregated as much as possible in there from what i could find
>> online.
>>
>> i've also set
>> CLASSPATH=/dream/oe1.6/dm8000/build/tmp/cross/mipsel/bin/ecj.jar:./
>>
>> when i run make, linking fails:
>>
>> /dream/oe1.6/dm8000/build/tmp/cross/mipsel/lib/gcc/mipsel-oe-
>> linux/4.4.4/../../../../mipsel-oe-linux/bin/ld: warning: cannot find entry
>> symbol __start; defaulting to 00000000004084b0
>> /dream/oe1.6/dm8000/build/tmp/cross/mipsel/lib/gcc/mipsel-oe-
>> linux/4.4.4/../../../../mipsel-oe-linux/lib/libgcj.a(dyn_load.o): In function
>> `GC_register_dynamic_libraries_dl_iterate_phdr':
>> /dream/oe1.6/dm8000/build/tmp/work/mipsel-oe-linux/gcc-cross-4.4.4-
>> r0.1/gcc-4.4.4/boehm-gc/dyn_load.c:454: undefined reference to `__data_start'
>> /dream/oe1.6/dm8000/build/tmp/cross/mipsel/lib/gcc/mipsel-oe-
>> linux/4.4.4/../../../../mipsel-oe-linux/lib/libgcj.a(os_dep.o): In function
>> `GC_register_data_segments':
>> /dream/oe1.6/dm8000/build/tmp/work/mipsel-oe-linux/gcc-cross-4.4.4-
>> r0.1/gcc-4.4.4/boehm-gc/os_dep.c:1450: undefined reference to `__data_start'
>> collect2: ld returned 1 exit status
>> make: *** [dumphd-static-new] Error 1
>>
>> i'd be grateful for any suggestions or hints.
>
> This looks completely broken: it seems to be trying to statically link
> against libgcj.  Try it without -non_shared.
>

To expound on this, the '-static-libgcj' option was created so that all 
the other things you have there would be unneeded.

I doubt you want any of: -shared-libgcc -Wl,-non_shared -lgcj 
-Wl,-call_shared -lstdc++ -Wl,--as-needed -lgcc_s -lpthread -lc -lm -ldl 
-lrt -Wl,--no-as-needed -Wl,-O1


Start off with -static-libgcj on a very simple 'hello-world' type 
program.  Then start adding all your other things in.

David Daney