Customer is running their application and getting the following error on
Solaris O/S using the JavaSoft Reference Implementation 1.1.8:

Aug 25 9:18:30 1999: ld.so.1: /work2/jaguar35/bin/jagsrv: fatal: relocation
error: file
/wok2/jaguar35/jdk/jdk_latest/lib/sparc/native_threads/libJdbcOdbc.so: symbol
makeCString:referenced symbol not found (libJdbcOdbc.so)

Looking at libJdbcOdbc.so which is located:

  /net/mizu.eng/export2/jdk/1.1.8/m/binary/solaris/lib/sparc/native_threads

You see that makeCString is not found:

    donald% ldd -d libJdbcOdbc.so
libodbcinst.so.1 => (file not found)
libodbc.so.1 => (file not found)
libthread.so.1 => /usr/lib/libthread.so.1
libdl.so.1 => /usr/lib/libdl.so.1
libc.so.1 => /usr/lib/libc.so.1
/usr/platform/SUNW,Ultra-1/lib/libc_psr.so.1
symbol not found: SQLAllocConnect (./libJdbcOdbc.so)
        ...
symbol not found: makeCString (./libJdbcOdbc.so)
symbol not found: makeCString (./libJdbcOdbc.so)

This symbol is located in libjava.so. If the JDK was built with
libJdbcOdbc.so having the dependency of libjava.so (build it
with "-z defs" argument to see which symbols not defined) then link
in correct library, the symbol would be defined when customer runs their app
and the library would be available.

Customer does a dlopen() of libjava.so in his library libjjdk11.7.so with
a scope of RTLD_LOCAL.

13018: 1: file=libjjdk117.so; dlopen() called from
file=/work2/jaguar35/lib/libjaf_r.so [ RTLD_LOCAL RTLD_LAZY ]
......
13018: 1: file=libjava.so; needed by /work2/jaguar35/lib/libjjdk117.so

Then later when libJdbcOdbc.so is accessed, it can't
see the symbols it needs from libjava.so because they have local scope,
resulting in above "relocation error."

Email from Rod Evans:

"When an object is dlopen'ed it has a `local' scope. This scope is also
given to any of its dependencies. Thus the `group' of objects loaded
as a result of one dlopen() all have the same scope and can find symbols
within each other. In your scenario you have two dlopen groups. Different
groups are not allowed to locate symbols between each other. Groups can
have the same objects, and you establish your objects from having the
correct dependencies."


Customer can not change the scope from RTLD_LOCAL to RTLD_GLOBAL as this
will cause symbol collisions with the other libraries he is using in his
app.

-------------------

Testcase:

test.c:

  #include <dlfcn.h>

  main()
  {
        if (dlopen("libjava.so", RTLD_LAZY) == 0) {
                printf("libjava.so failed: %s\n", dlerror());
                return (1);
        }
        if (dlopen("libJdbcOdbc.so", RTLD_LAZY) == 0) {
                printf("libJdbcOdbc.so failed: %s\n", dlerror());
                return (1);
        }
        return (0);
  }

** This will dlopen with a default of RTLD_LOCAL.**

TO COMPILE:

      donald%cc -o main main.c -ldl -lthread

TO SET UP LD_LIBRARY_PATH:

donald% echo $LD_LIBRARY_PATH
/net/mizu.eng/export2/jdk/1.1.8/m/binary/solaris/lib/sparc/native_threads:/home/margotm/lib

TO RUN PROGRAM AND GET OUTPUT:

  donald% main
  libJdbcOdbc.so failed: ld.so.1: main: fatal: relocation error: file
/net/mizu.eng/export2/jdk/1.1.8/m/binary/solaris/lib/sparc/native_threads/
  libJdbcOdbc.so: symbol makeCString: referenced symbol not found
  Segmentation Fault

After licJdbcOdbc.so is built with the dependency of libjava.so the above
program should work.

margot.miller@Eng 1999-09-03