Revert "Make wxMSW stack walking methods work with Unicode identifiers."

[wxWidgets.git] / include / wx / log.h

diff --git a/include/wx/log.h b/include/wx/log.h
index e3e1f54adf4c588df38a7c45800dfe5142cd626c..be0a245a491cc38545bf900be971cf5bc8a5360b 100644 (file)
--- a/include/wx/log.h
+++ b/include/wx/log.h
@@ -4,7 +4,6 @@
 // Author:      Vadim Zeitlin
 // Modified by:
 // Created:     29/01/98
-// RCS-ID:      $Id$
 // Copyright:   (c) 1998 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
@@ -13,6 +12,7 @@
 #define _WX_LOG_H_
 
 #include "wx/defs.h"
+#include "wx/cpp.h"
 
 // ----------------------------------------------------------------------------
 // types
@@ -1330,28 +1330,42 @@ WXDLLIMPEXP_BASE const wxChar* wxSysErrorMsg(unsigned long nErrCode = 0);
 // following arguments are not even evaluated which is good as it avoids
 // unnecessary overhead)
 //
-// Note: the strange if/else construct is needed to make the following code
+// Note: the strange (because executing at most once) for() loop because we
+//       must arrange for wxDO_LOG() to be at the end of the macro and using a
+//       more natural "if (IsLevelEnabled()) wxDO_LOG()" would result in wrong
+//       behaviour for the following code ("else" would bind to the wrong "if"):
 //
 //          if ( cond )
 //              wxLogError("!!!");
 //          else
 //              ...
 //
-//       work as expected, without it the second "else" would match the "if"
-//       inside wxLogError(). Unfortunately code like
+//       See also #11829 for the problems with other simpler approaches,
+//       notably the need for two macros due to buggy __LINE__ in MSVC.
 //
-//          if ( cond )
-//              wxLogError("!!!");
-//
-//       now provokes "suggest explicit braces to avoid ambiguous 'else'"
-//       warnings from g++ 4.3 and later with -Wparentheses on but they can be
-//       easily fixed by adding curly braces around wxLogError() and at least
-//       the code still does do the right thing.
+// Note 2: Unfortunately we can't use the same solution for all compilers
+//         because the loop-based one results in problems with MSVC6 due to its
+//         wrong (pre-C++98) rules for the scope of the variables declared
+//         inside the loop, as this prevents us from using wxLogXXX() in switch
+//         statement clauses ("initialization of loopvar skipped by case"). So
+//         for now, i.e. while we still support VC6, use the previous solution
+//         for it (FIXME-VC6).
+#ifdef __VISUALC6__
 #define wxDO_LOG_IF_ENABLED(level)                                            \
     if ( !wxLog::IsLevelEnabled(wxLOG_##level, wxLOG_COMPONENT) )             \
     {}                                                                        \
     else                                                                      \
         wxDO_LOG(level)
+#else
+#define wxDO_LOG_IF_ENABLED_HELPER(level, loopvar)                            \
+    for ( bool loopvar = false;                                               \
+          !loopvar && wxLog::IsLevelEnabled(wxLOG_##level, wxLOG_COMPONENT);  \
+          loopvar = true )                                                    \
+        wxDO_LOG(level)
+
+#define wxDO_LOG_IF_ENABLED(level)                                            \
+    wxDO_LOG_IF_ENABLED_HELPER(level, wxMAKE_UNIQUE_NAME(wxlogcheck))
+#endif
 
 // wxLogFatalError() is special as it can't be disabled
 #define wxLogFatalError wxDO_LOG(FatalError)