diff --git a/Makefile b/Makefile
index 42b754733ec..a7f3feefba6 100644
--- a/Makefile
+++ b/Makefile
@@ -600,7 +600,7 @@ $(libcppdir)/cppcheck.o: lib/cppcheck.cpp externals/picojson/picojson.h external
 $(libcppdir)/ctu.o: lib/ctu.cpp externals/tinyxml2/tinyxml2.h lib/astutils.h lib/check.h lib/config.h lib/ctu.h lib/errorlogger.h lib/errortypes.h lib/library.h lib/mathlib.h lib/path.h lib/smallvector.h lib/sourcelocation.h lib/standards.h lib/symboldatabase.h lib/templatesimplifier.h lib/token.h lib/tokenize.h lib/tokenlist.h lib/utils.h lib/vfvalue.h lib/xml.h
 	$(CXX) ${INCLUDE_FOR_LIB} $(CPPFLAGS) $(CXXFLAGS) -c -o $@ $(libcppdir)/ctu.cpp
 
-$(libcppdir)/errorlogger.o: lib/errorlogger.cpp externals/tinyxml2/tinyxml2.h lib/check.h lib/checkers.h lib/color.h lib/config.h lib/cppcheck.h lib/errorlogger.h lib/errortypes.h lib/library.h lib/mathlib.h lib/path.h lib/platform.h lib/settings.h lib/smallvector.h lib/standards.h lib/suppressions.h lib/templatesimplifier.h lib/token.h lib/tokenlist.h lib/utils.h lib/vfvalue.h lib/xml.h
+$(libcppdir)/errorlogger.o: lib/errorlogger.cpp externals/tinyxml2/tinyxml2.h lib/check.h lib/checkers.h lib/color.h lib/config.h lib/cppcheck.h lib/errorlogger.h lib/errortypes.h lib/library.h lib/mathlib.h lib/path.h lib/platform.h lib/settings.h lib/smallvector.h lib/sourcelocation.h lib/standards.h lib/suppressions.h lib/symboldatabase.h lib/templatesimplifier.h lib/token.h lib/tokenlist.h lib/utils.h lib/vfvalue.h lib/xml.h
 	$(CXX) ${INCLUDE_FOR_LIB} $(CPPFLAGS) $(CXXFLAGS) -c -o $@ $(libcppdir)/errorlogger.cpp
 
 $(libcppdir)/errortypes.o: lib/errortypes.cpp lib/config.h lib/errortypes.h lib/utils.h
diff --git a/lib/errorlogger.cpp b/lib/errorlogger.cpp
index d58c5abcbba..f4580fa2dc4 100644
--- a/lib/errorlogger.cpp
+++ b/lib/errorlogger.cpp
@@ -23,6 +23,7 @@
 #include "path.h"
 #include "settings.h"
 #include "suppressions.h"
+#include "symboldatabase.h"
 #include "token.h"
 #include "tokenlist.h"
 #include "utils.h"
@@ -35,6 +36,7 @@
 #include <cstring>
 #include <fstream>
 #include <iomanip>
+#include <numeric>
 #include <sstream>
 #include <string>
 #include <unordered_map>
@@ -106,6 +108,8 @@ ErrorMessage::ErrorMessage(const std::list<const Token*>& callstack, const Token
         file0 = list->getFiles()[0];
 
     setmsg(msg);
+
+    calculateWarningHash(callstack);
 }
 
 
@@ -126,7 +130,7 @@ ErrorMessage::ErrorMessage(const std::list<const Token*>& callstack, const Token
 
     setmsg(msg);
 
-    // hash = calculateWarningHash(list, hashWarning.str());
+    calculateWarningHash(callstack);
 }
 
 ErrorMessage::ErrorMessage(ErrorPath errorPath, const TokenList *tokenList, Severity severity, const char id[], const std::string &msg, const CWE &cwe, Certainty certainty)
@@ -159,7 +163,11 @@ ErrorMessage::ErrorMessage(ErrorPath errorPath, const TokenList *tokenList, Seve
 
     setmsg(msg);
 
-    // hash = calculateWarningHash(tokenList, hashWarning.str());
+    std::list<const Token*> callstack;
+    for (const ErrorPathItem& e: errorPath) {
+        callstack.push_back(e.first);
+    }
+    calculateWarningHash(callstack);
 }
 
 // TODO: improve errorhandling?
@@ -244,6 +252,58 @@ void ErrorMessage::setmsg(const std::string &msg)
     }
 }
 
+void ErrorMessage::calculateWarningHash(const std::list<const Token*>& callstack)
+{
+    if (callstack.empty())
+        return;
+    // Calculate a hash for this warning message
+    std::string hashString;
+    for (const Token* tok: callstack) {
+        if (!tok)
+            continue;
+        if (!tok->scope())
+            return; // might be a syntax error before scope info has been set
+        if (tok->scope()->isExecutable()) {
+            // Executable scope => include all tokens in the function => if the
+            // function is changed the hash is changed
+            for (const Token* t = tok; t; t = t->previous()) {
+                if (!t->scope()->isExecutable())
+                    break;
+                hashString += " " + t->str();
+            }
+            for (const Token* t = tok->next(); t; t = t->next()) {
+                if (!t->scope()->isExecutable())
+                    break;
+                hashString += " " + t->str();
+            }
+        } else {
+            // Non executable scope => include tokens in current statement => if the current statement is changed the hash is changed
+            for (const Token* t = tok; t; t = t->previous()) {
+                if (t->str() == ";")
+                    break;
+                if (t->scope() != tok->scope()) // stop on {} unless its an initializer
+                    break;
+                hashString += " " + t->str();
+            }
+            for (const Token* t = tok->next(); t; t = t->next()) {
+                hashString += " " + t->str();
+                if (t->str() == ";")
+                    break;
+                if (t->scope() != tok->scope()) // stop on {} unless its an initializer
+                    break;
+            }
+        }
+    }
+
+    hashString = id + '\n' + mShortMessage + '\n' + hashString;
+
+    // hash algorithm: sdbm
+    // any hash algorithm can be used but it has to be the same hash on different platforms and compilers
+    hash = std::accumulate(hashString.cbegin(), hashString.cend(), 0, [](std::size_t hash, char c) {
+        return static_cast<unsigned char>(c) + (hash << 6) + (hash << 16) - hash;
+    });
+}
+
 static void serializeString(std::string &oss, const std::string & str)
 {
     oss += std::to_string(str.length());
diff --git a/lib/errorlogger.h b/lib/errorlogger.h
index 97cc3e7f82e..b28fdba244e 100644
--- a/lib/errorlogger.h
+++ b/lib/errorlogger.h
@@ -209,6 +209,8 @@ class CPPCHECKLIB ErrorMessage {
 private:
     static std::string fixInvalidChars(const std::string& raw);
 
+    void calculateWarningHash(const std::list<const Token*>& callstack);
+
     /** Short message */
     std::string mShortMessage;
 
diff --git a/oss-fuzz/Makefile b/oss-fuzz/Makefile
index eeb795bd35c..e6966747958 100644
--- a/oss-fuzz/Makefile
+++ b/oss-fuzz/Makefile
@@ -270,7 +270,7 @@ $(libcppdir)/cppcheck.o: ../lib/cppcheck.cpp ../externals/picojson/picojson.h ..
 $(libcppdir)/ctu.o: ../lib/ctu.cpp ../externals/tinyxml2/tinyxml2.h ../lib/astutils.h ../lib/check.h ../lib/config.h ../lib/ctu.h ../lib/errorlogger.h ../lib/errortypes.h ../lib/library.h ../lib/mathlib.h ../lib/path.h ../lib/smallvector.h ../lib/sourcelocation.h ../lib/standards.h ../lib/symboldatabase.h ../lib/templatesimplifier.h ../lib/token.h ../lib/tokenize.h ../lib/tokenlist.h ../lib/utils.h ../lib/vfvalue.h ../lib/xml.h
 	$(CXX) ${LIB_FUZZING_ENGINE} $(CPPFLAGS) $(CXXFLAGS) -c -o $@ $(libcppdir)/ctu.cpp
 
-$(libcppdir)/errorlogger.o: ../lib/errorlogger.cpp ../externals/tinyxml2/tinyxml2.h ../lib/check.h ../lib/checkers.h ../lib/color.h ../lib/config.h ../lib/cppcheck.h ../lib/errorlogger.h ../lib/errortypes.h ../lib/library.h ../lib/mathlib.h ../lib/path.h ../lib/platform.h ../lib/settings.h ../lib/smallvector.h ../lib/standards.h ../lib/suppressions.h ../lib/templatesimplifier.h ../lib/token.h ../lib/tokenlist.h ../lib/utils.h ../lib/vfvalue.h ../lib/xml.h
+$(libcppdir)/errorlogger.o: ../lib/errorlogger.cpp ../externals/tinyxml2/tinyxml2.h ../lib/check.h ../lib/checkers.h ../lib/color.h ../lib/config.h ../lib/cppcheck.h ../lib/errorlogger.h ../lib/errortypes.h ../lib/library.h ../lib/mathlib.h ../lib/path.h ../lib/platform.h ../lib/settings.h ../lib/smallvector.h ../lib/sourcelocation.h ../lib/standards.h ../lib/suppressions.h ../lib/symboldatabase.h ../lib/templatesimplifier.h ../lib/token.h ../lib/tokenlist.h ../lib/utils.h ../lib/vfvalue.h ../lib/xml.h
 	$(CXX) ${LIB_FUZZING_ENGINE} $(CPPFLAGS) $(CXXFLAGS) -c -o $@ $(libcppdir)/errorlogger.cpp
 
 $(libcppdir)/errortypes.o: ../lib/errortypes.cpp ../lib/config.h ../lib/errortypes.h ../lib/utils.h
diff --git a/test/cli/other_test.py b/test/cli/other_test.py
index c48a0b50354..e1553dcc904 100644
--- a/test/cli/other_test.py
+++ b/test/cli/other_test.py
@@ -2666,7 +2666,7 @@ def test_xml_output(tmp_path):  # #13391 / #13485
 <results version="2">
     <cppcheck version="{}"/>
     <errors>
-        <error id="nullPointerRedundantCheck" severity="warning" msg="Either the condition &apos;p&apos; is redundant or there is possible null pointer dereference: p." verbose="Either the condition &apos;p&apos; is redundant or there is possible null pointer dereference: p." cwe="476" file0="{}" remark="boom">
+        <error id="nullPointerRedundantCheck" severity="warning" msg="Either the condition &apos;p&apos; is redundant or there is possible null pointer dereference: p." verbose="Either the condition &apos;p&apos; is redundant or there is possible null pointer dereference: p." cwe="476" hash="1842500187" file0="{}" remark="boom">
             <location file="{}" line="5" column="12" info="Null pointer dereference"/>
             <location file="{}" line="4" column="8" info="Assuming that condition &apos;p&apos; is not redundant"/>
             <symbol>p</symbol>