Make ECPG regression tests use native threading instead of pthreads, now that

ecpglib supports it.
Change configure (patch from Bruce) and msvc build system to no longer require
 pthreads on win32, since all parts of postgresql can be thread-safe using the
 native platform functions.

configure

@@ -3683,6 +3683,7 @@ IFS=$ac_save_IFS
 #
 echo "$as_me:$LINENO: checking allow thread-safe client libraries" >&5
 echo $ECHO_N "checking allow thread-safe client libraries... $ECHO_C" >&6
+if test "$PORTNAME" != "win32"; then
 
 pgac_args="$pgac_args enable_thread_safety"
 
@@ -3709,6 +3710,36 @@ else
 
 fi;
 
+else
+# Win32 should always use threads
+
+pgac_args="$pgac_args enable_thread_safety"
+
+# Check whether --enable-thread-safety or --disable-thread-safety was given.
+if test "${enable_thread_safety+set}" = set; then
+  enableval="$enable_thread_safety"
+
+  case $enableval in
+    yes)
+      :
+      ;;
+    no)
+      :
+      ;;
+    *)
+      { { echo "$as_me:$LINENO: error: no argument expected for --enable-thread-safety option" >&5
+echo "$as_me: error: no argument expected for --enable-thread-safety option" >&2;}
+   { (exit 1); exit 1; }; }
+      ;;
+  esac
+
+else
+  enable_thread_safety=yes
+
+fi;
+
+fi
+
 
 pgac_args="$pgac_args enable_thread_safety_force"
 
@@ -16701,8 +16732,8 @@ fi
 # For each platform, we need to know about any special compile and link
 # libraries, and whether the normal C function names are thread-safe.
 # See the comment at the top of src/port/thread.c for more information.
-#
-if test "$enable_thread_safety" = yes; then
+# WIN32 doesn't need the pthread tests;  it always uses threads
+if test "$enable_thread_safety" = yes -a "$PORTNAME" != "win32"; then
 
 
 
@@ -17236,6 +17267,7 @@ _LIBS="$LIBS"
 CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
 LIBS="$LIBS $PTHREAD_LIBS"
 
+if test "$PORTNAME" != "win32"; then
 if test "${ac_cv_header_pthread_h+set}" = set; then
   echo "$as_me:$LINENO: checking for pthread.h" >&5
 echo $ECHO_N "checking for pthread.h... $ECHO_C" >&6
@@ -17382,6 +17414,7 @@ echo "$as_me: error: pthread.h not found, required for --enable-thread-safety" >
 fi
 
 
+fi