From 7ebfb10edd4c74e1415c64ad7378e9740f6106f6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Marjam=C3=A4ki?= <daniel.marjamaki@gmail.com>
Date: Sun, 13 Nov 2016 18:19:51 +0100
Subject: [PATCH] Fixed #7806 (ValueFlow: better handling of subfunction with
 early return)

---
 lib/valueflow.cpp      |  9 ++++++---
 test/testvalueflow.cpp | 11 +++++++++++
 2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/lib/valueflow.cpp b/lib/valueflow.cpp
index 77f4c18d5..0fd26562f 100644
--- a/lib/valueflow.cpp
+++ b/lib/valueflow.cpp
@@ -1279,8 +1279,11 @@ static bool valueFlowForward(Token * const               startToken,
                 // goto '}'
                 tok2 = startToken1->link();
 
-                if (condAlwaysTrue && isReturnScope(tok2))
-                    return false;
+                if (isReturnScope(tok2)) {
+                    if (condAlwaysTrue)
+                        return false;
+                    removeValues(values, truevalues);
+                }
 
                 continue;
             }
@@ -2255,7 +2258,7 @@ static void valueFlowInjectParameter(TokenList* tokenlist, ErrorLogger* errorLog
     if (!varid2)
         return;
 
-    valueFlowForward(const_cast<Token*>(functionScope->classStart->next()), functionScope->classEnd, arg, varid2, argvalues, true, tokenlist, errorLogger, settings);
+    valueFlowForward(const_cast<Token*>(functionScope->classStart->next()), functionScope->classEnd, arg, varid2, argvalues, false, tokenlist, errorLogger, settings);
 }
 
 static void valueFlowSwitchVariable(TokenList *tokenlist, SymbolDatabase* symboldatabase, ErrorLogger *errorLogger, const Settings *settings)
diff --git a/test/testvalueflow.cpp b/test/testvalueflow.cpp
index 6a9f91f9a..273d8d0f8 100644
--- a/test/testvalueflow.cpp
+++ b/test/testvalueflow.cpp
@@ -1716,6 +1716,17 @@ private:
                "}";
         ASSERT_EQUALS(false, testValueOfX(code, 3U, 0));
 
+        code = "void f1(int x) {\n"
+               "    if (x == 0) return;\n"
+               "    int y = x;\n"
+               "}\n"
+               "\n"
+               "void f2() {\n"
+               "    f1(x&4);\n" // possible {0,4}
+               "}";
+        ASSERT_EQUALS(false, testValueOfX(code, 3U, 0));
+        ASSERT_EQUALS(true, testValueOfX(code, 3U, 4));
+
         code = "void f1(int x) { a=x; }\n"
                "void f2(int y) { f1(y<123); }\n";
         ASSERT_EQUALS(true, testValueOfX(code, 1U, 0));