C++: Fix preprocessor blocked macro bug.

By lexing the first token after a macro call (meaning: the token after
the closing parenthesis (which was passed to handleFunctionLikeMacro
which in turn pushed it back into the token buffer)), a token buffer
might be popped, which unblocks the macro that generated the actual
param pack. The effect was that if this happens in the expansion of a
recursive macro (with parameters!), the preprocessor ended up in an
infinite loop.

Task-number: QTCREATORBUG-9015
Task-number: QTCREATORBUG-9447

Change-Id: I0d83c59188ec15c4a948970e9fa944a17d765475
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>

src/libs/cplusplus/pp-engine.cpp

@@ -1048,7 +1048,7 @@ bool Preprocessor::handleIdentifier(PPToken *tk)
                                           argRefs);
         }
 
-        if (!handleFunctionLikeMacro(tk, macro, body, allArgTks, baseLine)) {
+        if (!handleFunctionLikeMacro(macro, body, allArgTks, baseLine)) {
             if (m_client && !idTk.expanded())
                 m_client->stopExpandingMacro(idTk.offset, *macro);
             return false;
@@ -1119,8 +1119,7 @@ bool Preprocessor::handleIdentifier(PPToken *tk)
     return true;
 }
 
-bool Preprocessor::handleFunctionLikeMacro(PPToken *tk,
-                                           const Macro *macro,
+bool Preprocessor::handleFunctionLikeMacro(const Macro *macro,
                                            QVector<PPToken> &body,
                                            const QVector<QVector<PPToken> > &actuals,
                                            unsigned baseLine)
@@ -1220,9 +1219,6 @@ bool Preprocessor::handleFunctionLikeMacro(PPToken *tk,
     body = expanded;
     body.squeeze();
 
-    // Next token to be lexed after the expansion.
-    pushToken(tk);
-
     return true;
 }
 
@@ -1479,9 +1475,9 @@ bool Preprocessor::collectActualArguments(PPToken *tk, QVector<QVector<PPToken>
         actuals->append(tokens);
     }
 
-    if (tk->is(T_RPAREN))
-        lex(tk);
-    //###TODO: else error message
+    if (!tk->is(T_RPAREN)) {
+        //###TODO: else error message
+    }
     return true;
 }
 

src/libs/cplusplus/pp-engine.h

@@ -205,8 +205,7 @@ private:
     void lex(PPToken *tk);
     void skipPreprocesorDirective(PPToken *tk);
     bool handleIdentifier(PPToken *tk);
-    bool handleFunctionLikeMacro(PPToken *tk,
-                                 const Macro *macro,
+    bool handleFunctionLikeMacro(const Macro *macro,
                                  QVector<PPToken> &body,
                                  const QVector<QVector<PPToken> > &actuals,
                                  unsigned lineRef);

tests/auto/cplusplus/preprocessor/data/recursive.2.cpp

@@ -0,0 +1,6 @@
+#define a(x) b(x) c(x)
+#define b(x) c(x) a(x)
+#define c(x) a(x) b(x)
+
+b(1)
+a(1)

tests/auto/cplusplus/preprocessor/data/recursive.2.out.cpp

@@ -0,0 +1,12 @@
+# 1 "data/recursive.2.cpp"
+
+
+
+
+# expansion begin 70,1 ~2 5:2 ~3 5:2 ~3 5:2 ~3 5:2 ~3 5:2 ~3 5:2 ~1
+b(1) c(1) b(1) b(1) a(1) b(1)
+# expansion end
+# expansion begin 75,1 ~2 6:2 ~3 6:2 ~3 6:2 ~3 6:2 ~3 6:2 ~3 6:2 ~1
+a(1) b(1) a(1) a(1) c(1) a(1)
+# expansion end
+# 7 "data/recursive.2.cpp"

tests/auto/cplusplus/preprocessor/tst_preprocessor.cpp

@@ -822,6 +822,8 @@ void tst_Preprocessor::comparisons_data()
         << "reserved.1.cpp" << "reserved.1.out.cpp" << "";
     QTest::newRow("recursive 1")
         << "recursive.1.cpp" << "recursive.1.out.cpp" << "";
+    QTest::newRow("recursive 2")
+        << "recursive.2.cpp" << "recursive.2.out.cpp" << "";
     QTest::newRow("macro_pounder_fn")
         << "macro_pounder_fn.c" << "" << "";
     QTest::newRow("macro_expand")