* Throughout, use __try/__except/__endtry blocks, rather than myfault

handler.
	* cygtls.cc (_cygtls::remove): Accommodate the fact that pathbufs
	has been moved from _local_storage to _cygtls.
	* cygtls.h (class tls_pathbuf): Add comment to hint to gendef usage
	of counters.  Change type of counters to uint32_t for clarity.
	Remove _cygtls as friend class.
	(struct _local_storage): Move pathbufs from here...
	(struct _cygtls): ...to here, allowing to access it from _sigbe.
	(class san): Only define on 32 bit.  Remove errno, _c_cnt and _w_cnt
	members.
	(san::setup): Drop parameter.  Don't initialize removed members.
	(san::leave): Don't set removed members.
	(class myfault): Only define on 32 bit.
	(myfault::faulted): Only keep implementation not taking any parameter.
	Drop argument in call to sebastian.setup.
	(__try/__leave/__except/__endtry): Implement to support real SEH.  For
	now stick to SJLJ on 32 bit.
	* dcrt0.cc (dll_crt0_0): Drop 64 bit call to
	exception::install_myfault_handler.
	* exception.h (exception_handler): Define with EXCEPTION_DISPOSITION
	as return type.
	(PDISPATCHER_CONTEXT): Define as void * on 32 bit.  Define as pointer
	to _DISPATCHER_CONTEXT on 64 bit.
	(class exception): Define separately for 32 and 64 bit.
	(exception::myfault): Add handler for myfault SEH handling on 64 bit.
	(exception::exception): Fix mangled method name to account for change
	in type of last parameter.
	(exception::install_myfault_handler): Remove.
	* exceptions.cc (exception::myfault_handle): Remove.
	(exception::myfault): New SEH handler for 64 bit.
	* gendef (_sigbe): Set tls_pathbuf counters to 0 explicitely when
	returning to the caller.
	* ntdll.h: Move a comment to a better place.
	(struct _SCOPE_TABLE): Define on 64 bit.
	* thread.cc (verifyable_object_isvalid): Remove gcc 4.7 workaround.
	* tls_pbuf.cc (tls_pbuf): Fix to accommodate new place of pathbufs.
	(tls_pathbuf::destroy): Change type of loop variables to uint32_t.
	* tls_pbuf.h (class tmp_pathbuf): Change type of buffer counters to
	uint32_t.  Accommodate new place of pathbufs.
	* tlsoffsets.h: Regenerate.
	* tlsoffsets64.h: Regenerate.

winsup/cygwin/exceptions.cc

@@ -341,38 +341,41 @@ void
 cygwin_exception::dumpstack ()
 {
   static bool already_dumped;
-  myfault efault;
-  if (efault.faulted ())
-    return;
 
-  if (already_dumped || cygheap->rlim_core == 0Ul)
-    return;
-  already_dumped = true;
-  open_stackdumpfile ();
-
-  if (e)
-    dump_exception ();
-
-  int i;
-
-  thestack.init (framep, 1, ctx);	/* Initialize from the input CONTEXT */
-#ifdef __x86_64__
-  small_printf ("Stack trace:\r\nFrame        Function    Args\r\n");
-#else
-  small_printf ("Stack trace:\r\nFrame     Function  Args\r\n");
-#endif
-  for (i = 0; i < 16 && thestack++; i++)
+  __try
     {
-      small_printf (_AFMT "  " _AFMT, thestack.sf.AddrFrame.Offset,
-		    thestack.sf.AddrPC.Offset);
-      for (unsigned j = 0; j < NPARAMS; j++)
-	small_printf ("%s" _AFMT, j == 0 ? " (" : ", ", thestack.sf.Params[j]);
-      small_printf (")\r\n");
+      if (already_dumped || cygheap->rlim_core == 0Ul)
+	return;
+      already_dumped = true;
+      open_stackdumpfile ();
+
+      if (e)
+	dump_exception ();
+
+      int i;
+
+      thestack.init (framep, 1, ctx);	/* Initialize from the input CONTEXT */
+#ifdef __x86_64__
+      small_printf ("Stack trace:\r\nFrame        Function    Args\r\n");
+#else
+      small_printf ("Stack trace:\r\nFrame     Function  Args\r\n");
+#endif
+      for (i = 0; i < 16 && thestack++; i++)
+	{
+	  small_printf (_AFMT "  " _AFMT, thestack.sf.AddrFrame.Offset,
+			thestack.sf.AddrPC.Offset);
+	  for (unsigned j = 0; j < NPARAMS; j++)
+	    small_printf ("%s" _AFMT, j == 0 ? " (" : ", ",
+			  thestack.sf.Params[j]);
+	  small_printf (")\r\n");
+	}
+      small_printf ("End of stack trace%s\n",
+		    i == 16 ? " (more stack frames may be present)" : "");
+      if (h)
+	NtClose (h);
     }
-  small_printf ("End of stack trace%s\n",
-	      i == 16 ? " (more stack frames may be present)" : "");
-  if (h)
-    NtClose (h);
+  __except (NO_ERROR) {}
+  __endtry
 }
 
 bool
@@ -549,40 +552,24 @@ rtl_unwind (exception_list *frame, PEXCEPTION_RECORD e)
 #endif /* __x86_64 */
 
 #ifdef __x86_64__
-/* myfault vectored exception handler */
-LONG
-exception::myfault_handle (LPEXCEPTION_POINTERS ep)
+/* myfault exception handler. */
+EXCEPTION_DISPOSITION
+exception::myfault (EXCEPTION_RECORD *e, exception_list *frame, CONTEXT *in,
+		    PDISPATCHER_CONTEXT dispatch)
 {
-  _cygtls& me = _my_tls;
-
-  if (me.andreas)
-    {
-      /* Only handle the minimum amount of exceptions the myfault handler
-	 was designed for. */
-      switch (ep->ExceptionRecord->ExceptionCode)
-	{
-	case STATUS_ACCESS_VIOLATION:
-	case STATUS_DATATYPE_MISALIGNMENT:
-#if 0
-	/* PAGE_GUARD-based stack commits are based on structured exception
-	   handling.  Short-circuiting STATUS_STACK_OVERFLOW in a vectored
-	   exception handler disables that, which can ultimately result in
-	   a spurious SEGV. */
-	case STATUS_STACK_OVERFLOW:
-#endif
-	case STATUS_ARRAY_BOUNDS_EXCEEDED:
-	  me.andreas->leave ();	/* Return from a "san" caught fault */
-	default:
-	  break;
-	}
-    }
-  return EXCEPTION_CONTINUE_SEARCH;
+  PSCOPE_TABLE table = (PSCOPE_TABLE) dispatch->HandlerData;
+  RtlUnwindEx (frame,
+	       (char *) dispatch->ImageBase + table->ScopeRecord[0].JumpTarget,
+	       e, 0, in, dispatch->HistoryTable);
+  /* NOTREACHED, make gcc happy. */
+  return ExceptionContinueSearch;
 }
-#endif /* __x86_64 */
+#endif
 
 /* Main exception handler. */
-int
-exception::handle (EXCEPTION_RECORD *e, exception_list *frame, CONTEXT *in, void *)
+EXCEPTION_DISPOSITION
+exception::handle (EXCEPTION_RECORD *e, exception_list *frame, CONTEXT *in,
+		   PDISPATCHER_CONTEXT dispatch)
 {
   static bool NO_COPY debugging;
   _cygtls& me = _my_tls;