LastErrorException broken on AIX

[skissane]

The following test program works fine on, e.g. Linux, but fails on AIX. LastErrorException is not thrown even though call sets errno.

Using GIT master JNA, commit: 2b8773a
oslevel: 7.1.0.0
java version "1.6.0"
Java(TM) SE Runtime Environment (build pap6460sr9fp2-20110627_03(SR9 FP2))
IBM J9 VM (build 2.4, JRE 1.6.0 IBM J9 2.4 AIX ppc64-64 jvmap6460sr9-20110624_85526 (JIT enabled, AOT enabled)
J9VM - 20110624_085526
JIT - r9_20101028_17488ifx17
GC - 20101027_AA)
JCL - 20110530_01

import com.sun.jna.*;
import java.util.*;

public class JNATest {
   public static void main(String[] args) {
      try {
         int rc = LibC.INSTANCE.open("/nonexistentfile-" + UUID.randomUUID(), 2, 0);
         System.err.println("TEST FAILED: Expected exception, instead got rc=" + rc);
      } catch (LastErrorException ex) {
         System.err.println("TEST PASSED");
      }
   }

   public interface LibC extends Library {
      public static final LibC INSTANCE = (LibC)Native.loadLibrary("c", LibC.class);
      int open(String pathname, int flags, int mode) throws LastErrorException;
   }
}

[skissane]

Cause: On AIX, errno is not thread safe unless _THREAD_SAFE_ERRNO is defined. (Read /usr/include/errno.h for details)

Solution: Add the line "#define _THREAD_SAFE_ERRNO" before every occurrence of "#include <errno.h>".
Doing so in ./native/dispatch.c is enough to get this test to pass.

For perfect correctness, might be necessary to do so in the other places where errno.h is included:
./native/testlib.c
./native/libffi/src/dlmalloc.c
./native/libffi/src/closures.c

Another option would be to change the build scripts to add -D_THREAD_SAFE_ERRNO when calling the C compiler on AIX. (I believe that defining this on all platforms, not just AIX, should be harmless.)

[twall]

It's probably best to add it to CDEFINES in the Makfile AIX section, e.g.

CDEFINES += -D_THREAD_SAFE_ERRNO

which will ensure it's defined everywhere.

Thanks for checking; contribution of the AIX natives would be welcome when you're done.