From 980ca39fe21acc5576835cefe1d376a55dc98192 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Marjam=C3=A4ki?= <daniel.marjamaki@gmail.com>
Date: Sat, 29 Apr 2017 08:25:55 +0200
Subject: [PATCH] valueFlowForward: better handling of sizeof() in rhs in
 assignments

---
 lib/valueflow.cpp      | 12 ++++++++----
 test/testvalueflow.cpp |  7 +++++++
 2 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/lib/valueflow.cpp b/lib/valueflow.cpp
index 549a5b059..ab96a34b1 100644
--- a/lib/valueflow.cpp
+++ b/lib/valueflow.cpp
@@ -1005,8 +1005,8 @@ static void valueFlowReverse(TokenList *tokenlist,
                 break;
         }
 
-        // skip sizeof..
-        if (tok2->str() == ")" && Token::Match(tok2->link()->previous(), "typeof|sizeof ("))
+        // skip sizeof etc..
+        if (tok2->str() == ")" && Token::Match(tok2->link()->previous(), "sizeof|typeof|typeid ("))
             tok2 = tok2->link();
 
         // goto label
@@ -1307,7 +1307,8 @@ static bool valueFlowForward(Token * const               startToken,
             return false;
         }
 
-        if (Token::Match(tok2, "sizeof|typeof|typeid ("))
+        // Skip sizeof etc
+        else if (Token::Match(tok2, "sizeof|typeof|typeid ("))
             tok2 = tok2->linkAt(1);
 
         else if (Token::simpleMatch(tok2, "else {")) {
@@ -1635,7 +1636,7 @@ static bool valueFlowForward(Token * const               startToken,
 
         else if (tok2->varId() == varid) {
             // bailout: assignment
-            if (Token::Match(tok2->previous(), "!!* %name% %op%") && tok2->next()->isAssignmentOp()) {
+            if (Token::Match(tok2->previous(), "!!* %name% %assign%")) {
                 // simplify rhs
                 for (Token *tok3 = tok2->tokAt(2); tok3; tok3 = tok3->next()) {
                     if (tok3->varId() == varid) {
@@ -1644,6 +1645,9 @@ static bool valueFlowForward(Token * const               startToken,
                             setTokenValue(tok3, *it, settings);
                     } else if (Token::Match(tok3, "++|--|?|:|;"))
                         break;
+                    // Skip sizeof etc
+                    else if (Token::Match(tok3, "sizeof|typeof|typeid ("))
+                        tok3 = tok3->linkAt(1);
                 }
                 if (settings->debugwarnings)
                     bailout(tokenlist, errorLogger, tok2, "assignment of " + tok2->str());
diff --git a/test/testvalueflow.cpp b/test/testvalueflow.cpp
index 00d111f94..ec823f36d 100644
--- a/test/testvalueflow.cpp
+++ b/test/testvalueflow.cpp
@@ -2422,6 +2422,13 @@ private:
                "}";
         values = tokenValues(code, "c .");
         ASSERT_EQUALS(true, values.size()==1U && values.front().isUninitValue());
+
+        code = "void f() {\n"
+               "    int **x;\n"
+               "    y += 10;\n"
+               "    x = dostuff(sizeof(*x)*y);\n"
+               "}";
+        ASSERT_EQUALS(0U, tokenValues(code, "x )").size());
     }
 };