From f803a18d5017bc5e2a5541c830f4a2c3c6831c62 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Marjam=C3=A4ki?= <daniel.marjamaki@gmail.com>
Date: Thu, 17 May 2012 07:26:57 +0200
Subject: [PATCH] Fixed #3749 (false positive: same expression on both sides of
 operator)

---
 lib/checkother.cpp | 11 +++++++++++
 test/testother.cpp |  9 +++++++++
 2 files changed, 20 insertions(+)

diff --git a/lib/checkother.cpp b/lib/checkother.cpp
index 2d950f3b9..9afc56051 100644
--- a/lib/checkother.cpp
+++ b/lib/checkother.cpp
@@ -3046,9 +3046,20 @@ void CheckOther::checkDuplicateExpression()
                     }
                 }
 
+                // If either variable token is an expanded macro then
+                // don't write the warning
+                if (tok->next()->isExpandedMacro() || tok->tokAt(3)->isExpandedMacro())
+                    continue;
+
                 duplicateExpressionError(tok->next(), tok->tokAt(3), tok->strAt(2));
             } else if (Token::Match(tok, ",|=|return|(|&&|%oror% %var% . %var% ==|!=|<=|>=|<|>|- %var% . %var% )|&&|%oror%|;|,") &&
                        tok->strAt(1) == tok->strAt(5) && tok->strAt(3) == tok->strAt(7)) {
+
+                // If either variable token is an expanded macro then
+                // don't write the warning
+                if (tok->next()->isExpandedMacro() || tok->tokAt(6)->isExpandedMacro())
+                    continue;
+
                 duplicateExpressionError(tok->next(), tok->tokAt(6), tok->strAt(4));
             }
         }
diff --git a/test/testother.cpp b/test/testother.cpp
index 3a159be53..bef1867fd 100644
--- a/test/testother.cpp
+++ b/test/testother.cpp
@@ -153,6 +153,7 @@ private:
         TEST_CASE(duplicateExpression2); // ticket #2730
         TEST_CASE(duplicateExpression3); // ticket #3317
         TEST_CASE(duplicateExpression4); // ticket #3354 (++)
+        TEST_CASE(duplicateExpression5); // ticket #3749 (macros with same values)
 
         TEST_CASE(alwaysTrueFalseStringCompare);
         TEST_CASE(checkPointerSizeof);
@@ -4218,6 +4219,14 @@ private:
         ASSERT_EQUALS("", errout.str());
     }
 
+    void duplicateExpression5() {  // #3749 - macros with same values
+        Preprocessor::macroChar = '$';
+        check("void f() {\n"
+              "    if ($a == $a) { }\n"
+              "}");
+        ASSERT_EQUALS("", errout.str());
+    }
+
     void alwaysTrueFalseStringCompare() {
         check_preprocess_suppress(
             "#define MACRO \"00FF00\"\n"