Enable thread testing outside the source tree.

configure

@@ -17904,7 +17904,7 @@ else
   cat >conftest.$ac_ext <<_ACEOF
 #line $LINENO "configure"
 #include "confdefs.h"
-#include "src/tools/thread/thread_test.c"
+#include "$srcdir/src/tools/thread/thread_test.c"
 _ACEOF
 rm -f conftest$ac_exeext
 if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&5

configure.in

 dnl Process this file with autoconf to produce a configure script.
-dnl $PostgreSQL: pgsql/configure.in,v 1.337 2004/04/27 19:51:12 momjian Exp $
+dnl $PostgreSQL: pgsql/configure.in,v 1.338 2004/04/27 20:06:52 momjian Exp $
 dnl
 dnl Developers, please strive to achieve this order:
 dnl
@@ -1188,7 +1188,7 @@ _CFLAGS="$CFLAGS"
 _LIBS="$LIBS"
 CFLAGS="$CFLAGS $PTHREAD_CFLAGS -DIN_CONFIGURE"
 LIBS="$LIBS $PTHREAD_LIBS"
-AC_TRY_RUN([#include "src/tools/thread/thread_test.c"],
+AC_TRY_RUN([#include "$srcdir/src/tools/thread/thread_test.c"],
   [AC_MSG_RESULT(yes)],
   [AC_MSG_RESULT(no)
   AC_MSG_ERROR([Thread test program failed.  Your platform is not thread-safe.  See 'config.log])],