diff --git a/lib/checkcondition.cpp b/lib/checkcondition.cpp
index 4776cbea38f..4c2909e251a 100644
--- a/lib/checkcondition.cpp
+++ b/lib/checkcondition.cpp
@@ -1846,6 +1846,42 @@ void CheckConditionImpl::pointerAdditionResultNotNullError(const Token *tok, con
     reportError(tok, Severity::warning, "pointerAdditionResultNotNull", "Comparison is wrong. Result of '" + s + "' can't be 0 unless there is pointer overflow, and pointer overflow is undefined behaviour.");
 }
 
+static bool checkBoolConditionalAssign(const Token* condTok, const Token* assignTok, bool& isRedundant)
+{
+    bool isNegation = false;
+    const Token* varTok = condTok;
+    if (condTok->isUnaryOp("!")) {
+        isNegation = true;
+        varTok = varTok->astOperand1();
+    } else if (condTok->isBinaryOp()) {
+        varTok = condTok->astOperand1();
+        if (varTok->hasKnownIntValue())
+            varTok = condTok->astOperand2();
+    }
+
+    const ValueType* vt = varTok->variable() ? varTok->variable()->valueType() : nullptr;
+    if (!(vt && vt->type == ValueType::Type::BOOL && !vt->pointer))
+        return false;
+
+    if (!(assignTok->astOperand1() && assignTok->astOperand1()->varId() == varTok->varId()))
+        return false;
+    if (!(assignTok->astOperand2() && assignTok->astOperand2()->hasKnownIntValue()))
+        return false;
+    const MathLib::bigint val = assignTok->astOperand2()->getKnownIntValue();
+    if (val < 0 || val > 1)
+        return false;
+    if (condTok->isBinaryOp()) {
+        if (!varTok->astSibling()->hasKnownIntValue())
+            return false;
+        const MathLib::bigint compVal = varTok->astSibling()->getKnownIntValue();
+        if (compVal < 0 || compVal > 1)
+            return false;
+        isNegation = (condTok->str() == "!=") == (compVal == 1);
+    }
+    isRedundant = (isNegation && val == 0) || (!isNegation && val == 1);
+    return true;
+}
+
 void CheckConditionImpl::checkDuplicateConditionalAssign()
 {
     if (!mSettings.severity.isEnabled(Severity::style) && !mSettings.isPremiumEnabled("duplicateConditionalAssign"))
@@ -1862,7 +1898,7 @@ void CheckConditionImpl::checkDuplicateConditionalAssign()
                 continue;
             const Token *blockTok = tok->linkAt(1)->next();
             const Token *condTok = tok->next()->astOperand2();
-            const bool isBoolVar = Token::Match(condTok, "!| %var%");
+            bool isBoolVar = Token::Match(condTok, "!| %var%");
             if (!isBoolVar && !Token::Match(condTok, "==|!="))
                 continue;
             if ((isBoolVar || condTok->str() == "!=") && Token::simpleMatch(blockTok->link(), "} else {"))
@@ -1875,21 +1911,8 @@ void CheckConditionImpl::checkDuplicateConditionalAssign()
             if (nextAfterAstRightmostLeaf(assignTok) != blockTok->link()->previous())
                 continue;
             bool isRedundant = false;
-            if (isBoolVar) {
-                const bool isNegation = condTok->str() == "!";
-                const Token* const varTok = isNegation ? condTok->next() : condTok;
-                const ValueType* vt = varTok->variable() ? varTok->variable()->valueType() : nullptr;
-                if (!(vt && vt->type == ValueType::Type::BOOL && !vt->pointer))
-                    continue;
-
-                if (!(assignTok->astOperand1() && assignTok->astOperand1()->varId() == varTok->varId()))
-                    continue;
-                if (!(assignTok->astOperand2() && assignTok->astOperand2()->hasKnownIntValue()))
-                    continue;
-                const MathLib::bigint val = assignTok->astOperand2()->getKnownIntValue();
-                if (val < 0 || val > 1)
-                    continue;
-                isRedundant = (isNegation && val == 0) || (!isNegation && val == 1);
+            if (checkBoolConditionalAssign(condTok, assignTok, isRedundant)) {
+                isBoolVar = true;
             } else { // comparison
                 if (!isSameExpression(
                         true, condTok->astOperand1(), assignTok->astOperand1(), mSettings, true, true))
@@ -1898,17 +1921,17 @@ void CheckConditionImpl::checkDuplicateConditionalAssign()
                         true, condTok->astOperand2(), assignTok->astOperand2(), mSettings, true, true))
                     continue;
             }
-            duplicateConditionalAssignError(condTok, assignTok, isRedundant);
+            duplicateConditionalAssignError(condTok, assignTok, isRedundant, isBoolVar);
         }
     }
 }
 
-void CheckConditionImpl::duplicateConditionalAssignError(const Token *condTok, const Token* assignTok, bool isRedundant)
+void CheckConditionImpl::duplicateConditionalAssignError(const Token *condTok, const Token* assignTok, bool isRedundant, bool isBoolVar)
 {
     ErrorPath errors;
     std::string msg = "Duplicate expression for the condition and assignment.";
     if (condTok && assignTok) {
-        if (condTok->str() == "==") {
+        if (condTok->str() == "==" && !isBoolVar) {
             msg = "Assignment '" + assignTok->expressionString() + "' is redundant with condition '" + condTok->expressionString() + "'.";
             errors.emplace_back(condTok, "Condition '" + condTok->expressionString() + "'");
             errors.emplace_back(assignTok, "Assignment '" + assignTok->expressionString() + "' is redundant");
@@ -1924,7 +1947,6 @@ void CheckConditionImpl::duplicateConditionalAssignError(const Token *condTok, c
         std::move(errors), Severity::style, "duplicateConditionalAssign", msg, CWE398, Certainty::normal);
 }
 
-
 void CheckConditionImpl::checkAssignmentInCondition()
 {
     if (!mSettings.severity.isEnabled(Severity::style) && !mSettings.isPremiumEnabled("assignmentInCondition"))
diff --git a/lib/checkcondition.h b/lib/checkcondition.h
index 232b2b5b340..4a4e1f22db1 100644
--- a/lib/checkcondition.h
+++ b/lib/checkcondition.h
@@ -176,7 +176,7 @@ class CPPCHECKLIB CheckConditionImpl : public CheckImpl {
     void invalidTestForOverflow(const Token* tok, const ValueType *valueType, const std::string &replace);
     void pointerAdditionResultNotNullError(const Token *tok, const Token *calc);
 
-    void duplicateConditionalAssignError(const Token *condTok, const Token* assignTok, bool isRedundant = false);
+    void duplicateConditionalAssignError(const Token *condTok, const Token* assignTok, bool isRedundant = false, bool isBoolVar = false);
 
     void assignmentInCondition(const Token *eq);
 
diff --git a/test/testcondition.cpp b/test/testcondition.cpp
index 6d62b644043..5d57ad3e312 100644
--- a/test/testcondition.cpp
+++ b/test/testcondition.cpp
@@ -6406,6 +6406,50 @@ class TestCondition : public TestFixture {
                       "[test.cpp:7:19]: note: Assignment 'b=false'\n"
                       "[test.cpp:7:13]: note: Condition '!b' is redundant\n",
                       errout_str());
+
+        check("void f(bool& b) {\n" // #14915
+              "    if (b == true)\n"
+              "        b = false;\n"
+              "}\n"
+              "void g(bool& b) {\n"
+              "    if (b == false)\n"
+              "        b = false;\n"
+              "}\n"
+              "void h(bool& b) {\n"
+              "    if (b != true)\n"
+              "        b = false;\n"
+              "}\n"
+              "void i(bool& b) {\n"
+              "    if (b != false)\n"
+              "        b = false;\n"
+              "}\n"
+              "void j(bool& b) {\n"
+              "    if (b == true)\n"
+              "        b = true;\n"
+              "}\n"
+              "void k(bool& b) {\n"
+              "    if (true == b)\n"
+              "        b = false;\n"
+              "}\n");
+        ASSERT_EQUALS("[test.cpp:2:11]: style: The statement 'if (b==true) b=false' is logically equivalent to 'b=false'. [duplicateConditionalAssign]\n"
+                      "[test.cpp:3:11]: note: Assignment 'b=false'\n"
+                      "[test.cpp:2:11]: note: Condition 'b==true' is redundant\n"
+                      "[test.cpp:6:11]: style: The statement 'if (b==false) b=false' is redundant. [duplicateConditionalAssign]\n"
+                      "[test.cpp:7:11]: note: Assignment 'b=false'\n"
+                      "[test.cpp:6:11]: note: Condition 'b==false' is redundant\n"
+                      "[test.cpp:10:11]: style: The statement 'if (b!=true) b=false' is redundant. [duplicateConditionalAssign]\n"
+                      "[test.cpp:11:11]: note: Assignment 'b=false'\n"
+                      "[test.cpp:10:11]: note: Condition 'b!=true' is redundant\n"
+                      "[test.cpp:14:11]: style: The statement 'if (b!=false) b=false' is logically equivalent to 'b=false'. [duplicateConditionalAssign]\n"
+                      "[test.cpp:15:11]: note: Assignment 'b=false'\n"
+                      "[test.cpp:14:11]: note: Condition 'b!=false' is redundant\n"
+                      "[test.cpp:18:11]: style: The statement 'if (b==true) b=true' is redundant. [duplicateConditionalAssign]\n"
+                      "[test.cpp:19:11]: note: Assignment 'b=true'\n"
+                      "[test.cpp:18:11]: note: Condition 'b==true' is redundant\n"
+                      "[test.cpp:22:14]: style: The statement 'if (true==b) b=false' is logically equivalent to 'b=false'. [duplicateConditionalAssign]\n"
+                      "[test.cpp:23:11]: note: Assignment 'b=false'\n"
+                      "[test.cpp:22:14]: note: Condition 'true==b' is redundant\n",
+                      errout_str());
     }
 
     void checkAssignmentInCondition() {