moc: Fix infinite recursion in macro substitution

When performing macro argument substitution, one should keep the set of
macro to exclude, else we can enter an infinite recursion.

Testcase:
 #define M1(A) A
 #define M2 M1(M2)

Task-number: QTBUG-29759
Change-Id: I564bbfed65e1c8599592eaf12c6d67285d2fd9ce
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Reviewed-by: Jędrzej Nowacki <jedrzej.nowacki@digia.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/src/tools/moc/preprocessor.cpp b/src/tools/moc/preprocessor.cpp
index 96b920b7cd..8f4b84a9c8 100644
--- a/src/tools/moc/preprocessor.cpp
+++ b/src/tools/moc/preprocessor.cpp
@@ -1,6 +1,7 @@
 /****************************************************************************
 **
 ** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
+** Copyright (C) 2013 Olivier Goffart <ogoffart@woboq.org>
 ** Contact: http://www.qt-project.org/legal
 **
 ** This file is part of the tools applications of the Qt Toolkit.
@@ -536,12 +537,14 @@ static Symbols tokenize(const QByteArray &input, int lineNum = 1, TokenizeMode m
     return symbols;
 }
 
-Symbols Preprocessor::macroExpand(Preprocessor *that, Symbols &toExpand, int &index, int lineNum, bool one)
+Symbols Preprocessor::macroExpand(Preprocessor *that, Symbols &toExpand, int &index,
+                                  int lineNum, bool one, const QSet<QByteArray> &excludeSymbols)
 {
     SymbolStack symbols;
     SafeSymbols sf;
     sf.symbols = toExpand;
     sf.index = index;
+    sf.excludedSymbols = excludeSymbols;
     symbols.push(sf);
 
     Symbols result;
@@ -664,7 +667,7 @@ Symbols Preprocessor::macroExpandIdentifier(Preprocessor *that, SymbolStack &sym
                     if (i == macro.symbols.size() - 1 || macro.symbols.at(i + 1).token != PP_HASHHASH) {
                         Symbols arg = arguments.at(index);
                         int idx = 1;
-                        expansion += macroExpand(that, arg, idx, lineNum, false);
+                        expansion += macroExpand(that, arg, idx, lineNum, false, symbols.excludeSymbols());
                     } else {
                         expansion += arguments.at(index);
                     }