From 1b86615a69f389b4621c83406f20b651e8d7d8bc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Marjam=C3=A4ki?= <daniel.marjamaki@gmail.com>
Date: Thu, 12 Dec 2013 11:44:07 +0100
Subject: [PATCH] Uninitialized variables: Fixed false positive for 'p=malloc;
 if (p) {}'

---
 lib/checkuninitvar.cpp | 4 ++--
 test/testuninitvar.cpp | 6 ++++++
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/lib/checkuninitvar.cpp b/lib/checkuninitvar.cpp
index 126a0ae5c..eced88f57 100644
--- a/lib/checkuninitvar.cpp
+++ b/lib/checkuninitvar.cpp
@@ -1703,7 +1703,7 @@ bool CheckUninitVar::isVariableUsage(const Token *vartok, bool pointer, bool all
 
             } else if (Token::Match(start->previous(), "if|while|for")) {
                 // control-flow statement reading the variable "by value"
-                return true;
+                return !alloc;
             }
         }
     }
@@ -1766,7 +1766,7 @@ bool CheckUninitVar::isVariableUsage(const Token *vartok, bool pointer, bool all
 
     bool unknown = false;
     if (pointer && CheckNullPointer::isPointerDeRef(vartok, unknown)) {
-        // pointer is allocated
+        // pointer is allocated - dereferencing it is ok.
         if (alloc)
             return false;
 
diff --git a/test/testuninitvar.cpp b/test/testuninitvar.cpp
index 67ba8cbf2..6eac6c5ec 100644
--- a/test/testuninitvar.cpp
+++ b/test/testuninitvar.cpp
@@ -3272,6 +3272,12 @@ private:
                         "}\n");
         ASSERT_EQUALS("", errout.str());
 
+        checkUninitVar2("void f() {\n"
+                        "    char *s = malloc(100);\n"
+                        "    if (s != NULL) { }\n"
+                        "}\n");
+        ASSERT_EQUALS("", errout.str());
+
         // function parameter (treat it as initialized until malloc is used)
         checkUninitVar2("int f(int *p) {\n"
                         "    if (*p == 1) {}\n" // no error