winedbg: Show some info for msvcrt C++ exceptions.

programs/winedbg/debugger.h

@@ -141,6 +141,15 @@ struct dbg_breakpoint
     struct expr*        condition;
 };
 
+/* used for C++ exceptions in msvcrt
+ * parameters:
+ * [0] CXX_FRAME_MAGIC
+ * [1] pointer to exception object
+ * [2] pointer to type
+ */
+#define CXX_EXCEPTION                       0xe06d7363
+#define CXX_FRAME_MAGIC                     0x19930520
+
 /* Wine extension; Windows doesn't have a name for this code.  This is an
    undocumented exception understood by MS VC debugger, allowing the program
    to name a particular thread.  Search google.com or deja.com for "0x406d1388"

programs/winedbg/tgt_active.c

@@ -381,6 +381,14 @@ static DWORD dbg_handle_exception(const EXCEPTION_RECORD* rec, BOOL first_chance
 	case EXCEPTION_FLT_STACK_CHECK:
             dbg_printf("floating point stack check");
             break;
+        case CXX_EXCEPTION:
+            if(rec->NumberParameters == 3 && rec->ExceptionInformation[0] == CXX_FRAME_MAGIC)
+                dbg_printf("C++ exception(object = 0x%08lx, type = 0x%08lx)",
+                           rec->ExceptionInformation[1], rec->ExceptionInformation[2]);
+            else
+                dbg_printf("C++ exception with strange parameter count %d or magic 0x%08lx",
+                           rec->NumberParameters, rec->ExceptionInformation[0]);
+            break;
         default:
             dbg_printf("0x%08x", rec->ExceptionCode);
             break;