Re: [GCC 4.4.0 / 4.4.1] GCJ - ecj1: undefined symbol: JvRunMainName, In function `_Jv_platform_nanotime()': undefined reference to "clock_gettime"

[Andrew Haley <aph@redhat.com>]

On 07/23/2009 11:38 PM, Piotr D. Kaczorowski wrote:
> 
> Hello there!
> 
> I'd like to build GCC 4.4.1 with GCJ on Centos 5.3 and have some
> problems with that.
> 
> 
> Description:
> 
> I'm using vanilla gcc source with gmp-4.2.4 and mpfr-2.3.2.
> 
> This is my configuration line:
> ./configure --program-suffix=44 --enable-languages=c,c++,java
> --with-ecj-jar=/usr/src/ecj/ecj.jar
> 
> ecj.jar is from FC11. GCC 4.4 with GCJ works on that system.

Hmm.  The usual ecj.jar is the one in:

 $ cksum /usr/share/java/ecj.jar
3248650573 1442090 /usr/share/java/ecj.jar

It's worth checking that.

> Problems:
> 
> 1) undefined symbol: JvRunMainName
> 
> [piotr@localhost gcj-3]$ gcj44 Foo.java
> /usr/local/libexec/gcc/i686-pc-linux-gnu/4.4.1/ecj1: symbol lookup
> error: /usr/local/libexec/gcc/i686-pc-linux-gnu/4.4.1/ecj1: undefined
> symbol: JvRunMainName

Hard to say.  Maybe a LD_LIBRARY_PATH issue?  Have you moved ecj
or its libraries from where it was installed?  Try

ldd /usr/local/libexec/gcc/i686-pc-linux-gnu/4.4.1/ecj1

> 2) static linking (http://gcc.gnu.org/wiki/Statically_linking_libgcj)
> 
> Small program:
> public class Foo
> {
>   public static void main(String args[])
>   {
>       System.out.println("Hello.");
>   }
> }
> 
> [piotr@localhost gcj-3]$ gcj -c Foo.java
> [piotr@localhost gcj-3]$ gcj --main=Foo -save-temps Foo.java
> [piotr@localhost gcj-3]$ gcc -o Foo Foo.o Foomain.i -shared-libgcc
> -Wl,-non_shared -lgcj -Wl,-call_shared -lsupc++ -Wl,--as-needed -lz
> -lgcc_s -lpthread -lc -lm -ldl -Wl,--no-as-needed
> /usr/local/lib/libgcj.a(posix.o): In function `_Jv_platform_nanotime()':
> posix.cc:(.text+0xa0): undefined reference to `clock_gettime'
> collect2: ld returned 1 exit status

I don't really know.  Maybe you just need to refer to libc before libgcj.

Statically linking libgcj is *not* something you can just do from a recipe.
You have to understand how linking works, and when finding problems like
this you have to be prepared to investigate yourself.

Andrew.