diff --git a/test/fixture.cpp b/test/fixture.cpp
index 1a72724a0..fd8ac2ffa 100644
--- a/test/fixture.cpp
+++ b/test/fixture.cpp
@@ -403,9 +403,7 @@ void TestFixture::reportErr(const ErrorMessage &msg)
     if (msg.severity == Severity::internal)
         return;
     const std::string errormessage(msg.toString(mVerbose, mTemplateFormat, mTemplateLocation));
-    // TODO: remove the unique error handling?
-    if (errout.str().find(errormessage) == std::string::npos)
-        errout << errormessage << std::endl;
+    errout << errormessage << std::endl;
 }
 
 void TestFixture::setTemplateFormat(const std::string &templateFormat)
diff --git a/test/testautovariables.cpp b/test/testautovariables.cpp
index b48f49fe7..8ba129815 100644
--- a/test/testautovariables.cpp
+++ b/test/testautovariables.cpp
@@ -663,7 +663,10 @@ private:
               "    struct S s;\n"
               "    g(&s);\n"
               "}");
-        ASSERT_EQUALS("[test.cpp:4]: (error) Address of local auto-variable assigned to a function parameter.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:4]: (error) Address of local auto-variable assigned to a function parameter.\n"
+            "[test.cpp:4]: (error) Address of local auto-variable assigned to a function parameter.\n",   // duplicate
+            errout.str());
     }
 
     void testinvaliddealloc() {
@@ -2508,7 +2511,8 @@ private:
               "    }\n"
               "};");
         ASSERT_EQUALS(
-            "[test.cpp:6] -> [test.cpp:6] -> [test.cpp:6] -> [test.cpp:4] -> [test.cpp:7]: (error) Non-local variable 'm' will use object that points to local variable 'x'.\n",
+            "[test.cpp:6] -> [test.cpp:6] -> [test.cpp:6] -> [test.cpp:4] -> [test.cpp:7]: (error) Non-local variable 'm' will use object that points to local variable 'x'.\n"
+            "[test.cpp:6] -> [test.cpp:6] -> [test.cpp:6] -> [test.cpp:4] -> [test.cpp:7]: (error) Non-local variable 'm' will use object that points to local variable 'x'.\n", // duplicate
             errout.str());
 
         check("std::vector<int>::iterator f(std::vector<int> v) {\n"
@@ -3795,7 +3799,8 @@ private:
               "    return v;\n"
               "}");
         ASSERT_EQUALS(
-            "[test.cpp:3] -> [test.cpp:3] -> [test.cpp:2] -> [test.cpp:4]: (error) Returning object that points to local variable 'i' that will be invalid when returning.\n",
+            "[test.cpp:3] -> [test.cpp:3] -> [test.cpp:2] -> [test.cpp:4]: (error) Returning object that points to local variable 'i' that will be invalid when returning.\n"
+            "[test.cpp:3] -> [test.cpp:3] -> [test.cpp:2] -> [test.cpp:4]: (error) Returning object that points to local variable 'i' that will be invalid when returning.\n", // duplicate
             errout.str());
 
         check("std::vector<int*> f() {\n"
@@ -3804,7 +3809,8 @@ private:
               "    return v;\n"
               "}");
         ASSERT_EQUALS(
-            "[test.cpp:3] -> [test.cpp:3] -> [test.cpp:2] -> [test.cpp:4]: (error) Returning object that points to local variable 'i' that will be invalid when returning.\n",
+            "[test.cpp:3] -> [test.cpp:3] -> [test.cpp:2] -> [test.cpp:4]: (error) Returning object that points to local variable 'i' that will be invalid when returning.\n"
+            "[test.cpp:3] -> [test.cpp:3] -> [test.cpp:2] -> [test.cpp:4]: (error) Returning object that points to local variable 'i' that will be invalid when returning.\n", // duplicate
             errout.str());
 
         check("std::vector<int*> f() {\n"
@@ -3812,7 +3818,8 @@ private:
               "    return {&i, &i};\n"
               "}");
         ASSERT_EQUALS(
-            "[test.cpp:3] -> [test.cpp:3] -> [test.cpp:2] -> [test.cpp:3]: (error) Returning object that points to local variable 'i' that will be invalid when returning.\n",
+            "[test.cpp:3] -> [test.cpp:3] -> [test.cpp:2] -> [test.cpp:3]: (error) Returning object that points to local variable 'i' that will be invalid when returning.\n"
+            "[test.cpp:3] -> [test.cpp:3] -> [test.cpp:2] -> [test.cpp:3]: (error) Returning object that points to local variable 'i' that will be invalid when returning.\n", // duplicate
             errout.str());
 
         check("std::vector<int*> f(int& x) {\n"
diff --git a/test/testbool.cpp b/test/testbool.cpp
index 17115bd9e..c16477fb6 100644
--- a/test/testbool.cpp
+++ b/test/testbool.cpp
@@ -269,7 +269,10 @@ private:
               "    if ((5 && x)==3 || (8 && x)==9)\n"
               "        a++;\n"
               "}");
-        ASSERT_EQUALS("[test.cpp:2]: (warning) Comparison of a boolean expression with an integer other than 0 or 1.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:2]: (warning) Comparison of a boolean expression with an integer other than 0 or 1.\n"
+            "[test.cpp:2]: (warning) Comparison of a boolean expression with an integer other than 0 or 1.\n",   // duplicate
+            errout.str());
 
         check("void f(int x) {\n"
               "    if ((5 && x)!=3)\n"
diff --git a/test/testfunctions.cpp b/test/testfunctions.cpp
index e223e74b0..636df6e8d 100644
--- a/test/testfunctions.cpp
+++ b/test/testfunctions.cpp
@@ -215,7 +215,10 @@ private:
         check("void TDataModel::forceRowRefresh(int row) {\n"
               "    emit dataChanged(index(row, 0), index(row, columnCount() - 1));\n"
               "}");
-        ASSERT_EQUALS("[test.cpp:2]: (style) Obsolescent function 'index' called. It is recommended to use 'strchr' instead.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:2]: (style) Obsolescent function 'index' called. It is recommended to use 'strchr' instead.\n"
+            "[test.cpp:2]: (style) Obsolescent function 'index' called. It is recommended to use 'strchr' instead.\n",   // duplicate
+            errout.str());
     }
 
     void prohibitedFunctions_rindex() {
diff --git a/test/testnullpointer.cpp b/test/testnullpointer.cpp
index 217e72405..f2ad99a9e 100644
--- a/test/testnullpointer.cpp
+++ b/test/testnullpointer.cpp
@@ -3431,7 +3431,10 @@ private:
               "    char* s = 0;\n"
               "    printf(\"%s\", s);\n"
               "}");
-        ASSERT_EQUALS("[test.cpp:3]: (error) Null pointer dereference: s\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (error) Null pointer dereference: s\n"
+            "[test.cpp:3]: (error) Null pointer dereference\n",
+            errout.str());
 
         check("void f() {\n"
               "    char *s = 0;\n"
@@ -3453,7 +3456,10 @@ private:
               "    char* s = 0;\n"
               "    printf(\"%u%s\", 123, s);\n"
               "}");
-        ASSERT_EQUALS("[test.cpp:3]: (error) Null pointer dereference: s\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (error) Null pointer dereference: s\n"
+            "[test.cpp:3]: (error) Null pointer dereference\n",
+            errout.str());
 
 
         check("void f() {\n"
@@ -3496,12 +3502,18 @@ private:
         check("void f(char* s) {\n"
               "    sscanf(s, \"%s\", 0);\n"
               "}");
-        ASSERT_EQUALS("[test.cpp:2]: (error) Null pointer dereference\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:2]: (error) Null pointer dereference\n"
+            "[test.cpp:2]: (error) Null pointer dereference\n",   // duplicate
+            errout.str());
 
         check("void f() {\n"
               "    scanf(\"%d\", 0);\n"
               "}");
-        ASSERT_EQUALS("[test.cpp:2]: (error) Null pointer dereference\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:2]: (error) Null pointer dereference\n"
+            "[test.cpp:2]: (error) Null pointer dereference\n",   // duplicate
+            errout.str());
 
         check("void f(char* foo) {\n"
               "    char location[200];\n"
@@ -3520,7 +3532,11 @@ private:
               "    int* iVal = 0;\n"
               "    sscanf(dummy, \"%d\", iVal);\n"
               "}");
-        ASSERT_EQUALS("[test.cpp:3]: (error) Null pointer dereference: iVal\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (error) Null pointer dereference: iVal\n"
+            "[test.cpp:3]: (error) Null pointer dereference\n"
+            "[test.cpp:3]: (error) Null pointer dereference\n",   // duplicate
+            errout.str());
 
         check("void f(char *dummy) {\n"
               "    int* iVal;\n"
@@ -3537,7 +3553,10 @@ private:
         check("void f(char* dummy) {\n"
               "    sscanf(dummy, \"%*d%u\", 0);\n"
               "}");
-        ASSERT_EQUALS("[test.cpp:2]: (error) Null pointer dereference\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:2]: (error) Null pointer dereference\n"
+            "[test.cpp:2]: (error) Null pointer dereference\n",   // duplicate
+            errout.str());
     }
 
     void nullpointer_in_return() {
@@ -4258,7 +4277,10 @@ private:
         check("void f(char *p = 0) {\n"
               "    std::cout << p ? *p : 0;\n" // Due to operator precedence, this is equivalent to: (std::cout << p) ? *p : 0;
               "}");
-        ASSERT_EQUALS("[test.cpp:2]: (warning) Possible null pointer dereference if the default parameter value is used: p\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:2]: (warning) Possible null pointer dereference if the default parameter value is used: p\n"
+            "[test.cpp:2]: (warning) Possible null pointer dereference if the default parameter value is used: p\n",   // duplicate
+            errout.str());
 
         check("void f(int *p = 0) {\n"
               "    std::cout << (p ? *p : 0);\n"
diff --git a/test/testother.cpp b/test/testother.cpp
index 20228dfa9..8e33d2d09 100644
--- a/test/testother.cpp
+++ b/test/testother.cpp
@@ -3111,8 +3111,11 @@ private:
               "void an();\n"
               "void h();");
         ASSERT_EQUALS("[test.cpp:131]: (style) Variable 'tm' can be declared as pointer to const\n"
+                      "[test.cpp:131]: (style) Variable 'tm' can be declared as pointer to const\n" // duplicate
                       "[test.cpp:136]: (style) Variable 'af' can be declared as pointer to const\n"
-                      "[test.cpp:137]: (style) Variable 'ag' can be declared as pointer to const\n",
+                      "[test.cpp:137]: (style) Variable 'ag' can be declared as pointer to const\n"
+                      "[test.cpp:136]: (style) Variable 'af' can be declared as pointer to const\n" // duplicate
+                      "[test.cpp:137]: (style) Variable 'ag' can be declared as pointer to const\n", // duplicate
                       errout.str());
 
         check("class C\n"
@@ -3327,14 +3330,21 @@ private:
               "    if (d)\n"
               "        d->f();\n"
               "}\n");
-        ASSERT_EQUALS("[test.cpp:4]: (style) Variable 'd' can be declared as pointer to const\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:4]: (style) Variable 'd' can be declared as pointer to const\n"
+            "[test.cpp:4]: (style) Variable 'd' can be declared as pointer to const\n"   // duplicate
+            "[test.cpp:4]: (style) Variable 'd' can be declared as pointer to const\n",   // duplicate
+            errout.str());
 
         check("void g(const int*);\n"
               "void f(const std::vector<int*>&v) {\n"
               "    for (int* i : v)\n"
               "        g(i);\n"
               "}\n");
-        ASSERT_EQUALS("[test.cpp:3]: (style) Variable 'i' can be declared as pointer to const\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (style) Variable 'i' can be declared as pointer to const\n"
+            "[test.cpp:3]: (style) Variable 'i' can be declared as pointer to const\n",   // duplicate
+            errout.str());
 
         check("struct A {\n" // #11225
               "    A();\n"
@@ -3660,7 +3670,10 @@ private:
               "    for (const auto& h : v)\n"
               "        if (h) {}\n"
               "}\n");
-        ASSERT_EQUALS("[test.cpp:5]: (style) Variable 'h' can be declared as pointer to const\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:5]: (style) Variable 'h' can be declared as pointer to const\n"
+            "[test.cpp:5]: (style) Variable 'h' can be declared as pointer to const\n",   // duplicate
+            errout.str());
 
         check("void f(const std::vector<int*>& v) {\n"
               "    for (const auto& p : v)\n"
@@ -3668,7 +3681,10 @@ private:
               "    for (const auto* p : v)\n"
               "        if (p == nullptr) {}\n"
               "}\n");
-        ASSERT_EQUALS("[test.cpp:2]: (style) Variable 'p' can be declared as pointer to const\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:2]: (style) Variable 'p' can be declared as pointer to const\n"
+            "[test.cpp:2]: (style) Variable 'p' can be declared as pointer to const\n",   // duplicate
+            errout.str());
 
         check("void f(std::vector<int*>& v) {\n"
               "    for (const auto& p : v)\n"
@@ -3681,7 +3697,8 @@ private:
               "        if (p == nullptr) {}\n"
               "}\n");
         ASSERT_EQUALS("[test.cpp:1]: (style) Parameter 'v' can be declared as reference to const\n"
-                      "[test.cpp:2]: (style) Variable 'p' can be declared as pointer to const\n",
+                      "[test.cpp:2]: (style) Variable 'p' can be declared as pointer to const\n"
+                      "[test.cpp:2]: (style) Variable 'p' can be declared as pointer to const\n", // duplicate
                       errout.str());
 
         check("void f(std::vector<const int*>& v) {\n"
@@ -3772,7 +3789,9 @@ private:
               "    v.clear();\n"
               "}\n");
         ASSERT_EQUALS("[test.cpp:2]: (style) Variable 'p' can be declared as pointer to const\n"
-                      "[test.cpp:5]: (style) Variable 'p' can be declared as pointer to const\n",
+                      "[test.cpp:2]: (style) Variable 'p' can be declared as pointer to const\n" // duplicate
+                      "[test.cpp:5]: (style) Variable 'p' can be declared as pointer to const\n"
+                      "[test.cpp:5]: (style) Variable 'p' can be declared as pointer to const\n", // duplicate
                       errout.str());
 
         check("void f() {\n"
@@ -3835,7 +3854,8 @@ private:
               "    g(1, p);\n"
               "    h(p);\n"
               "}\n");
-        ASSERT_EQUALS("[test.cpp:3]: (style) Parameter 'p' can be declared as pointer to const\n",
+        ASSERT_EQUALS("[test.cpp:3]: (style) Parameter 'p' can be declared as pointer to const\n"
+                      "[test.cpp:3]: (style) Parameter 'p' can be declared as pointer to const\n", // duplicate
                       errout.str());
 
         check("void f(int, const int*);\n"
@@ -3982,7 +4002,8 @@ private:
               "    void* p = &i;\n"
               "    std::cout << p << '\\n';\n"
               "}\n");
-        ASSERT_EQUALS("[test.cpp:2]: (style) Variable 'p' can be declared as pointer to const\n",
+        ASSERT_EQUALS("[test.cpp:2]: (style) Variable 'p' can be declared as pointer to const\n"
+                      "[test.cpp:2]: (style) Variable 'p' can be declared as pointer to const\n", // duplicate
                       errout.str());
 
         check("struct S { const T* t; };\n" // #12206
@@ -3998,6 +4019,8 @@ private:
               "    delete[] b;\n"
               "}\n");
         ASSERT_EQUALS("[test.cpp:1]: (style) Parameter 'a1' can be declared as pointer to const\n"
+                      "[test.cpp:1]: (style) Parameter 'a2' can be declared as pointer to const\n"
+                      "[test.cpp:1]: (style) Parameter 'a1' can be declared as pointer to const\n"
                       "[test.cpp:1]: (style) Parameter 'a2' can be declared as pointer to const\n",
                       errout.str());
     }
@@ -6657,7 +6680,10 @@ private:
         check("Vector func(int vec1) {\n"
               "    return fabs(vec1 & vec1 & vec1);\n"
               "}");
-        ASSERT_EQUALS("[test.cpp:2]: (style) Same expression on both sides of '&'.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:2]: (style) Same expression on both sides of '&'.\n"
+            "[test.cpp:2]: (style) Same expression on both sides of '&'.\n",   // duplicate
+            errout.str());
 
     }
 
@@ -7668,7 +7694,8 @@ private:
               "    int end   = x->first;\n"
               "}");
         ASSERT_EQUALS("[test.cpp:4] -> [test.cpp:3]: (style, inconclusive) Same expression used in consecutive assignments of 'start' and 'end'.\n"
-                      "[test.cpp:2]: (style) Parameter 'x' can be declared as pointer to const\n",
+                      "[test.cpp:2]: (style) Parameter 'x' can be declared as pointer to const\n"
+                      "[test.cpp:2]: (style) Parameter 'x' can be declared as pointer to const\n", // duplicate
                       errout.str());
 
         check("struct SW { int first; };\n"
@@ -7677,7 +7704,8 @@ private:
               "    int end   = x->first;\n"
               "}");
         ASSERT_EQUALS("[test.cpp:4] -> [test.cpp:3]: (style, inconclusive) Same expression used in consecutive assignments of 'start' and 'end'.\n"
-                      "[test.cpp:2]: (style) Parameter 'x' can be declared as pointer to const\n",
+                      "[test.cpp:2]: (style) Parameter 'x' can be declared as pointer to const\n"
+                      "[test.cpp:2]: (style) Parameter 'x' can be declared as pointer to const\n", // duplicate
                       errout.str());
 
         check("struct Foo { int f() const; };\n"
@@ -7880,7 +7908,11 @@ private:
               "  if (*p < 0) continue;\n"
               "  if ((*p > 0)) {}\n"
               "}\n");
-        ASSERT_EQUALS("[test.cpp:3]: (style) Variable 'p' can be declared as pointer to const\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (style) Variable 'p' can be declared as pointer to const\n"
+            "[test.cpp:3]: (style) Variable 'p' can be declared as pointer to const\n"   // duplicate
+            "[test.cpp:3]: (style) Variable 'p' can be declared as pointer to const\n",   // duplicate
+            errout.str());
 
         check("void f() {\n"
               "  int val = 0;\n"
@@ -7890,7 +7922,9 @@ private:
               "}\n");
         TODO_ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) The comparison '*p < 0' is always false.\n"
                            "[test.cpp:2] -> [test.cpp:4]: (style) The comparison '*p > 0' is always false.\n",
-                           "[test.cpp:3]: (style) Variable 'p' can be declared as pointer to const\n",
+                           "[test.cpp:3]: (style) Variable 'p' can be declared as pointer to const\n"
+                           "[test.cpp:3]: (style) Variable 'p' can be declared as pointer to const\n" // duplicate
+                           "[test.cpp:3]: (style) Variable 'p' can be declared as pointer to const\n", // duplicate
                            errout.str());
 
         check("void f() {\n"
@@ -8554,7 +8588,11 @@ private:
               "  ptr = otherPtr;\n"
               "  free(otherPtr - xx - 1);\n"
               "}");
-        ASSERT_EQUALS("[test.cpp:2]: (style) Variable 'ptr' can be declared as pointer to const\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:2]: (style) Variable 'ptr' can be declared as pointer to const\n"
+            "[test.cpp:2]: (style) Variable 'ptr' can be declared as pointer to const\n"   // duplicate
+            "[test.cpp:2]: (style) Variable 'ptr' can be declared as pointer to const\n",   // duplicate
+            errout.str());
     }
 
     void checkRedundantCopy() {
@@ -9131,14 +9169,20 @@ private:
               "  state_t *x = NULL;\n"
               "  x = dostuff();\n"
               "}");
-        ASSERT_EQUALS("test.cpp:2:style:Variable 'x' can be declared as pointer to const\n", errout.str());
+        ASSERT_EQUALS(
+            "test.cpp:2:style:Variable 'x' can be declared as pointer to const\n"
+            "test.cpp:2:style:Variable 'x' can be declared as pointer to const\n",   // duplicate
+            errout.str());
 
         check("void f() {\n"
               "  state_t *x;\n"
               "  x = NULL;\n"
               "  x = dostuff();\n"
               "}");
-        ASSERT_EQUALS("test.cpp:2:style:Variable 'x' can be declared as pointer to const\n", errout.str());
+        ASSERT_EQUALS(
+            "test.cpp:2:style:Variable 'x' can be declared as pointer to const\n"
+            "test.cpp:2:style:Variable 'x' can be declared as pointer to const\n",   // duplicate
+            errout.str());
 
         check("int foo() {\n" // #4420
               "    int x;\n"
@@ -9272,7 +9316,9 @@ private:
               "    }\n"
               "}");
         ASSERT_EQUALS("test.cpp:2:style:The scope of the variable 'p' can be reduced.\n"
-                      "test.cpp:2:style:Variable 'p' can be declared as pointer to const\n",
+                      "test.cpp:2:style:Variable 'p' can be declared as pointer to const\n"
+                      "test.cpp:2:style:Variable 'p' can be declared as pointer to const\n" // duplicate
+                      "test.cpp:2:style:Variable 'p' can be declared as pointer to const\n", // duplicate
                       errout.str());
 
         check("void foo() {\n"
@@ -9364,14 +9410,20 @@ private:
               "   a = (void*)0;\n"
               "   a = p;\n"
               "}");
-        ASSERT_EQUALS("[test.cpp:2]: (style) Variable 'a' can be declared as pointer to const\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:2]: (style) Variable 'a' can be declared as pointer to const\n"
+            "[test.cpp:2]: (style) Variable 'a' can be declared as pointer to const\n",   // duplicate
+            errout.str());
 
         check("void f() {\n"
               "   void* a;\n"
               "   a = (void*)0U;\n"
               "   a = p;\n"
               "}");
-        ASSERT_EQUALS("[test.cpp:2]: (style) Variable 'a' can be declared as pointer to const\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:2]: (style) Variable 'a' can be declared as pointer to const\n"
+            "[test.cpp:2]: (style) Variable 'a' can be declared as pointer to const\n",   // duplicate
+            errout.str());
     }
 
     void redundantVarAssignment_struct() {
@@ -9628,7 +9680,10 @@ private:
               "    int *p = NULL;\n"
               "    p = dostuff();\n"
               "}");
-        ASSERT_EQUALS("test.cpp:2:style:Variable 'p' can be declared as pointer to const\n", errout.str());
+        ASSERT_EQUALS(
+            "test.cpp:2:style:Variable 'p' can be declared as pointer to const\n"
+            "test.cpp:2:style:Variable 'p' can be declared as pointer to const\n",   // duplicate
+            errout.str());
 
         // "trivial" initialization => do not warn
         check("void f() {\n"
@@ -10611,7 +10666,10 @@ private:
         check("void f() {\n"
               "  int x = x = y + 1;\n"
               "}", "test.c");
-        ASSERT_EQUALS("[test.c:2]: (warning) Redundant assignment of 'x' to itself.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.c:2]: (warning) Redundant assignment of 'x' to itself.\n"
+            "[test.c:2]: (warning) Redundant assignment of 'x' to itself.\n",   // duplicate
+            errout.str());
     }
 
     void testEvaluationOrderMacro() {
@@ -11427,7 +11485,9 @@ private:
         ASSERT_EQUALS(
             "[test.cpp:2] -> [test.cpp:4] -> [test.cpp:3] -> [test.cpp:5] -> [test.cpp:6]: (error) Comparing pointers that point to different objects\n"
             "[test.cpp:4]: (style) Variable 'xp' can be declared as pointer to const\n"
-            "[test.cpp:5]: (style) Variable 'yp' can be declared as pointer to const\n",
+            "[test.cpp:5]: (style) Variable 'yp' can be declared as pointer to const\n"
+            "[test.cpp:4]: (style) Variable 'xp' can be declared as pointer to const\n" // duplicate
+            "[test.cpp:5]: (style) Variable 'yp' can be declared as pointer to const\n", // duplicate
             errout.str());
 
         check("bool f() {\n"
@@ -11450,7 +11510,9 @@ private:
         ASSERT_EQUALS(
             "[test.cpp:1] -> [test.cpp:5] -> [test.cpp:1] -> [test.cpp:6] -> [test.cpp:7]: (error) Comparing pointers that point to different objects\n"
             "[test.cpp:5]: (style) Variable 'xp' can be declared as pointer to const\n"
-            "[test.cpp:6]: (style) Variable 'yp' can be declared as pointer to const\n",
+            "[test.cpp:6]: (style) Variable 'yp' can be declared as pointer to const\n"
+            "[test.cpp:5]: (style) Variable 'xp' can be declared as pointer to const\n" // duplicate
+            "[test.cpp:6]: (style) Variable 'yp' can be declared as pointer to const\n", // duplicate
             errout.str());
 
         check("struct A {int data;};\n"
@@ -11464,7 +11526,9 @@ private:
         ASSERT_EQUALS(
             "[test.cpp:2] -> [test.cpp:3] -> [test.cpp:5] -> [test.cpp:2] -> [test.cpp:4] -> [test.cpp:6] -> [test.cpp:7]: (error) Comparing pointers that point to different objects\n"
             "[test.cpp:5]: (style) Variable 'xp' can be declared as pointer to const\n"
-            "[test.cpp:6]: (style) Variable 'yp' can be declared as pointer to const\n",
+            "[test.cpp:6]: (style) Variable 'yp' can be declared as pointer to const\n"
+            "[test.cpp:5]: (style) Variable 'xp' can be declared as pointer to const\n" // duplicate
+            "[test.cpp:6]: (style) Variable 'yp' can be declared as pointer to const\n", // duplicate
             errout.str());
 
         check("bool f(int * xp, int* yp) {\n"
@@ -11490,7 +11554,9 @@ private:
               "    return xp > yp;\n"
               "}");
         ASSERT_EQUALS("[test.cpp:3]: (style) Variable 'xp' can be declared as pointer to const\n"
-                      "[test.cpp:4]: (style) Variable 'yp' can be declared as pointer to const\n",
+                      "[test.cpp:4]: (style) Variable 'yp' can be declared as pointer to const\n"
+                      "[test.cpp:3]: (style) Variable 'xp' can be declared as pointer to const\n" // duplicate
+                      "[test.cpp:4]: (style) Variable 'yp' can be declared as pointer to const\n", // duplicate
                       errout.str());
 
         check("bool f(const int * xp, const int* yp) {\n"
@@ -11522,7 +11588,9 @@ private:
               "    return xp > yp;\n"
               "}");
         ASSERT_EQUALS("[test.cpp:5]: (style) Variable 'xp' can be declared as pointer to const\n"
-                      "[test.cpp:6]: (style) Variable 'yp' can be declared as pointer to const\n",
+                      "[test.cpp:6]: (style) Variable 'yp' can be declared as pointer to const\n"
+                      "[test.cpp:5]: (style) Variable 'xp' can be declared as pointer to const\n" // duplicate
+                      "[test.cpp:6]: (style) Variable 'yp' can be declared as pointer to const\n", // duplicate
                       errout.str());
 
         check("struct S { int i; };\n" // #11576
diff --git a/test/testsimplifytypedef.cpp b/test/testsimplifytypedef.cpp
index 8d3f0bb88..089d3474b 100644
--- a/test/testsimplifytypedef.cpp
+++ b/test/testsimplifytypedef.cpp
@@ -1619,7 +1619,8 @@ private:
 
         checkSimplifyTypedef(code);
         ASSERT_EQUALS_WITHOUT_LINENUMBERS(
-            "[test.cpp:3]: (debug) valueflow.cpp:6541:(valueFlow) bailout: valueFlowAfterCondition: bailing in conditional block\n",
+            "[test.cpp:3]: (debug) valueflow.cpp:6541:(valueFlow) bailout: valueFlowAfterCondition: bailing in conditional block\n"
+            "[test.cpp:3]: (debug) valueflow.cpp:6541:(valueFlow) bailout: valueFlowAfterCondition: bailing in conditional block\n", // duplicate
             errout.str());
     }
 
diff --git a/test/testsingleexecutor.cpp b/test/testsingleexecutor.cpp
index d769e0b05..6abdcf239 100644
--- a/test/testsingleexecutor.cpp
+++ b/test/testsingleexecutor.cpp
@@ -348,7 +348,10 @@ private:
         check(2, 2,
               "#include \"" + inc_h.name() + "\"");
         // these are not actually made unique by the implementation. That needs to be done by the given ErrorLogger
-        ASSERT_EQUALS("[" + inc_h.name() + ":3]: (error) Null pointer dereference: (int*)0\n", errout.str());
+        ASSERT_EQUALS(
+            "[" + inc_h.name() + ":3]: (error) Null pointer dereference: (int*)0\n"
+            "[" + inc_h.name() + ":3]: (error) Null pointer dereference: (int*)0\n",
+            errout.str());
     }
 
     // TODO: test whole program analysis
diff --git a/test/teststl.cpp b/test/teststl.cpp
index 190978c9c..1b26e57eb 100644
--- a/test/teststl.cpp
+++ b/test/teststl.cpp
@@ -312,7 +312,10 @@ private:
                     "  std::string s;\n"
                     "  x = s.begin() + 1;\n"
                     "}");
-        ASSERT_EQUALS("test.cpp:3:error:Out of bounds access in expression 's.begin()+1' because 's' is empty.\n", errout.str());
+        ASSERT_EQUALS(
+            "test.cpp:3:error:Out of bounds access in expression 's.begin()+1' because 's' is empty.\n"
+            "test.cpp:3:error:Out of bounds access in expression 's.begin()+1' because 's' is empty.\n",   // duplicate
+            errout.str());
 
         checkNormal("void f(int x) {\n"
                     "  std::string s;\n"
@@ -1720,7 +1723,8 @@ private:
               "    {\n"
               "    }\n"
               "}");
-        ASSERT_EQUALS("[test.cpp:5]: (error) Iterators of different containers 'l1' and 'l2' are used together.\n",
+        ASSERT_EQUALS("[test.cpp:5]: (error) Iterators of different containers 'l1' and 'l2' are used together.\n"
+                      "[test.cpp:5]: (error) Iterators of different containers 'l1' and 'l2' are used together.\n", // duplicate
                       errout.str());
     }
 
@@ -3723,7 +3727,11 @@ private:
                            "    if (f.x.size() == 0) {}\n"
                            "}";
         check(code, false, Standards::CPP03);
-        ASSERT_EQUALS("[test.cpp:10]: (performance) Possible inefficient checking for 'x' emptiness.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:10]: (performance) Possible inefficient checking for 'x' emptiness.\n"
+            "[test.cpp:10]: (performance) Possible inefficient checking for 'x' emptiness.\n",   // duplicate
+            errout.str());
+
         check(code);
         ASSERT_EQUALS("", errout.str());
     }
@@ -3741,7 +3749,10 @@ private:
                            "    if (zzz->x.size() > 0) { }\n"
                            "}";
         check(code, false, Standards::CPP03);
-        ASSERT_EQUALS("[test.cpp:10]: (performance) Possible inefficient checking for 'x' emptiness.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:10]: (performance) Possible inefficient checking for 'x' emptiness.\n"
+            "[test.cpp:10]: (performance) Possible inefficient checking for 'x' emptiness.\n",   // duplicate
+            errout.str());
 
         code = "namespace N {\n"
                "    class Zzz {\n"
@@ -3755,7 +3766,11 @@ private:
                "    if (zzz->x.size() > 0) { }\n"
                "}";
         check(code, false, Standards::CPP03);
-        ASSERT_EQUALS("[test.cpp:10]: (performance) Possible inefficient checking for 'x' emptiness.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:10]: (performance) Possible inefficient checking for 'x' emptiness.\n"
+            "[test.cpp:10]: (performance) Possible inefficient checking for 'x' emptiness.\n",   // duplicate
+            errout.str());
+
         check(code);
         ASSERT_EQUALS("", errout.str());
     }
diff --git a/test/testsymboldatabase.cpp b/test/testsymboldatabase.cpp
index a0965e3a8..b59ed1fbf 100644
--- a/test/testsymboldatabase.cpp
+++ b/test/testsymboldatabase.cpp
@@ -3071,7 +3071,10 @@ private:
         check("testing::testing()\n"
               "{\n"
               "}");
-        ASSERT_EQUALS("[test.cpp:1]: (debug) Executable scope 'testing' with unknown function.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:1]: (debug) Executable scope 'testing' with unknown function.\n"
+            "[test.cpp:1]: (debug) Executable scope 'testing' with unknown function.\n", // duplicate
+            errout.str());
     }
 
     void symboldatabase5() {
@@ -3194,7 +3197,9 @@ private:
         check("::y(){x}");
 
         ASSERT_EQUALS("[test.cpp:1]: (debug) Executable scope 'y' with unknown function.\n"
-                      "[test.cpp:1]: (debug) valueFlowConditionExpressions bailout: Skipping function due to incomplete variable x\n", errout.str());
+                      "[test.cpp:1]: (debug) valueFlowConditionExpressions bailout: Skipping function due to incomplete variable x\n"
+                      "[test.cpp:1]: (debug) Executable scope 'y' with unknown function.\n", // duplicate
+                      errout.str());
     }
 
     void symboldatabase20() {
diff --git a/test/testunusedvar.cpp b/test/testunusedvar.cpp
index e9c50edda..a4237aefa 100644
--- a/test/testunusedvar.cpp
+++ b/test/testunusedvar.cpp
@@ -2018,7 +2018,10 @@ private:
                               "{\n"
                               "    int i = 0;\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n"
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("void foo()\n"
                               "{\n"
@@ -2092,13 +2095,19 @@ private:
                               "{\n"
                               "    bool i = false;\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n"
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("void foo()\n"
                               "{\n"
                               "    bool i = true;\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n"
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("void foo()\n"
                               "{\n"
@@ -2119,43 +2128,64 @@ private:
                               "    undefined i = 0;\n"
                               "}\n",
                               "test.c");
-        ASSERT_EQUALS("[test.c:3]: (style) Variable 'i' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.c:3]: (style) Variable 'i' is assigned a value that is never used.\n"
+            "[test.c:3]: (style) Variable 'i' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("void foo()\n"
                               "{\n"
                               "    int i = undefined;\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n"
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("void foo()\n"
                               "{\n"
                               "    int * i = Data;\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n"
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("void foo()\n"
                               "{\n"
                               "    void * i = Data;\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n"
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("void foo()\n"
                               "{\n"
                               "    const void * i = Data;\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n"
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("void foo()\n"
                               "{\n"
                               "    struct S * i = DATA;\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n"
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("void foo()\n"
                               "{\n"
                               "    const struct S * i = DATA;\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n"
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("void foo()\n"
                               "{\n"
@@ -2173,14 +2203,20 @@ private:
                               "{\n"
                               "    undefined * i = X;\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n"
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("void foo()\n"
                               "{\n"
                               "    int i = 0;\n"
                               "    int j = i;\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:4]: (style) Variable 'j' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:4]: (style) Variable 'j' is assigned a value that is never used.\n"
+            "[test.cpp:4]: (style) Variable 'j' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("void foo()\n"
                               "{\n"
@@ -2204,13 +2240,19 @@ private:
                               "{\n"
                               "    char *i = \"123456789\";\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n"
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("void foo()\n"
                               "{\n"
                               "    int i = 0;\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n"
+            "[test.cpp:3]: (style) Variable 'i' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("void foo()\n"
                               "{\n"
@@ -2444,7 +2486,10 @@ private:
         functionVariableUsage("void foo(int j = 0) {\n" // #5985 - default function parameters should not affect checking results
                               "    int i = 0;\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:2]: (style) Variable 'i' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:2]: (style) Variable 'i' is assigned a value that is never used.\n"
+            "[test.cpp:2]: (style) Variable 'i' is assigned a value that is never used.\n", // duplicate
+            errout.str());
         // extracttests.enable
     }
 
@@ -2901,7 +2946,9 @@ private:
                               "}");
         ASSERT_EQUALS("[test.cpp:7]: (style) Variable 'i' is assigned a value that is never used.\n"
                       "[test.cpp:3]: (style) Unused variable: i\n"
-                      "[test.cpp:5]: (style) Unused variable: i\n", errout.str());
+                      "[test.cpp:5]: (style) Unused variable: i\n"
+                      "[test.cpp:7]: (style) Variable 'i' is assigned a value that is never used.\n", // duplicate
+                      errout.str());
 
         functionVariableUsage("void foo(int x)\n"
                               "{\n"
@@ -3547,7 +3594,10 @@ private:
                               "void A::DoSomething(void) {\n"
                               "    const std::string x = Bar();\n"  // <- warning
                               "}");
-        ASSERT_EQUALS("[test.cpp:16]: (style) Variable 'x' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:16]: (style) Variable 'x' is assigned a value that is never used.\n"
+            "[test.cpp:16]: (style) Variable 'x' is assigned a value that is never used.\n", // duplicate
+            errout.str());
     }
 
     void localvar50() { // #6261, #6542
@@ -3729,13 +3779,19 @@ private:
                               "    int i = 0, j = 1;\n"
                               "    return i;\n"
                               "}\n");
-        ASSERT_EQUALS("[test.cpp:2]: (style) Variable 'j' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:2]: (style) Variable 'j' is assigned a value that is never used.\n"
+            "[test.cpp:2]: (style) Variable 'j' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("int f() {\n"
                               "    int i = 0, j = 1;\n"
                               "    return j;\n"
                               "}\n");
-        ASSERT_EQUALS("[test.cpp:2]: (style) Variable 'i' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:2]: (style) Variable 'i' is assigned a value that is never used.\n"
+            "[test.cpp:2]: (style) Variable 'i' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("void f() {\n" // #10846
                               "    int i = 1; while (i) { i = g(); }\n"
@@ -3975,7 +4031,9 @@ private:
                               "    int *b = &a;\n"
                               "}");
         ASSERT_EQUALS("[test.cpp:4]: (style) Variable 'b' is assigned a value that is never used.\n"
-                      "[test.cpp:3]: (style) Unused variable: a\n", errout.str());
+                      "[test.cpp:3]: (style) Unused variable: a\n"
+                      "[test.cpp:4]: (style) Variable 'b' is assigned a value that is never used.\n", // duplicate
+                      errout.str());
 
         functionVariableUsage("void foo()\n"
                               "{\n"
@@ -3983,7 +4041,9 @@ private:
                               "    int *b = a;\n"
                               "}");
         ASSERT_EQUALS("[test.cpp:4]: (style) Variable 'b' is assigned a value that is never used.\n"
-                      "[test.cpp:3]: (style) Unused variable: a\n", errout.str());
+                      "[test.cpp:3]: (style) Unused variable: a\n"
+                      "[test.cpp:4]: (style) Variable 'b' is assigned a value that is never used.\n", // duplicate
+                      errout.str());
 
         functionVariableUsage("void foo()\n"
                               "{\n"
@@ -4061,14 +4121,20 @@ private:
                               "{\n"
                               "    int *b = &a;\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:4]: (style) Variable 'b' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:4]: (style) Variable 'b' is assigned a value that is never used.\n"
+            "[test.cpp:4]: (style) Variable 'b' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         // a is not a local variable and b is aliased to it
         functionVariableUsage("void foo(int a)\n"
                               "{\n"
                               "    int *b = &a;\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:3]: (style) Variable 'b' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (style) Variable 'b' is assigned a value that is never used.\n"
+            "[test.cpp:3]: (style) Variable 'b' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         // a is not a local variable and b is aliased to it
         functionVariableUsage("class A\n"
@@ -4079,7 +4145,10 @@ private:
                               "        int *b = &a;\n"
                               "    }\n"
                               "};");
-        ASSERT_EQUALS("[test.cpp:6]: (style) Variable 'b' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:6]: (style) Variable 'b' is assigned a value that is never used.\n"
+            "[test.cpp:6]: (style) Variable 'b' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("int a;\n"
                               "void foo()\n"
@@ -4287,7 +4356,8 @@ private:
                               "    *d = 0;\n"
                               "}");
         ASSERT_EQUALS("[test.cpp:5]: (style) Variable 'c' is assigned a value that is never used.\n"
-                      "[test.cpp:3]: (style) Unused variable: a\n",
+                      "[test.cpp:3]: (style) Unused variable: a\n"
+                      "[test.cpp:5]: (style) Variable 'c' is assigned a value that is never used.\n", // duplicate
                       errout.str());
 
         functionVariableUsage("void foo()\n"
@@ -4332,8 +4402,11 @@ private:
                               "    b[-10] = 0;\n"
                               "    int * c = b - 10;\n"
                               "}");
-        ASSERT_EQUALS(// TODO "[test.cpp:4]: (style) Variable 'a' is assigned a value that is never used.\n"
-            "[test.cpp:5]: (style) Variable 'c' is assigned a value that is never used.\n", errout.str());
+        TODO_ASSERT_EQUALS(
+            "[test.cpp:4]: (style) Variable 'a' is assigned a value that is never used.\n",
+            "[test.cpp:5]: (style) Variable 'c' is assigned a value that is never used.\n"
+            "[test.cpp:5]: (style) Variable 'c' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("void foo()\n"
                               "{\n"
@@ -4389,7 +4462,9 @@ private:
                               "    struct S * s = (struct S *)a;\n"
                               "}");
         ASSERT_EQUALS("[test.cpp:5]: (style) Variable 's' is assigned a value that is never used.\n"
-                      "[test.cpp:4]: (style) Unused variable: a\n", errout.str());
+                      "[test.cpp:4]: (style) Unused variable: a\n"
+                      "[test.cpp:5]: (style) Variable 's' is assigned a value that is never used.\n", // duplicate
+                      errout.str());
 
         functionVariableUsage("struct S { char c[100]; };\n"
                               "void foo()\n"
@@ -4398,7 +4473,9 @@ private:
                               "    const struct S * s = (const struct S *)a;\n"
                               "}");
         ASSERT_EQUALS("[test.cpp:5]: (style) Variable 's' is assigned a value that is never used.\n"
-                      "[test.cpp:4]: (style) Unused variable: a\n", errout.str());
+                      "[test.cpp:4]: (style) Unused variable: a\n"
+                      "[test.cpp:5]: (style) Variable 's' is assigned a value that is never used.\n", // duplicate
+                      errout.str());
 
         functionVariableUsage("struct S { char c[100]; };\n"
                               "void foo()\n"
@@ -4407,7 +4484,9 @@ private:
                               "    struct S * s = static_cast<struct S *>(a);\n"
                               "}");
         ASSERT_EQUALS("[test.cpp:5]: (style) Variable 's' is assigned a value that is never used.\n"
-                      "[test.cpp:4]: (style) Unused variable: a\n", errout.str());
+                      "[test.cpp:4]: (style) Unused variable: a\n"
+                      "[test.cpp:5]: (style) Variable 's' is assigned a value that is never used.\n", // duplicate
+                      errout.str());
 
         functionVariableUsage("struct S { char c[100]; };\n"
                               "void foo()\n"
@@ -4416,7 +4495,9 @@ private:
                               "    const struct S * s = static_cast<const struct S *>(a);\n"
                               "}");
         ASSERT_EQUALS("[test.cpp:5]: (style) Variable 's' is assigned a value that is never used.\n"
-                      "[test.cpp:4]: (style) Unused variable: a\n", errout.str());
+                      "[test.cpp:4]: (style) Unused variable: a\n"
+                      "[test.cpp:5]: (style) Variable 's' is assigned a value that is never used.\n", // duplicate
+                      errout.str());
 
         functionVariableUsage("int a[10];\n"
                               "void foo()\n"
@@ -4474,7 +4555,10 @@ private:
                               "{\n"
                               "    int * a = &ab.a;\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:4]: (style) Variable 'a' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:4]: (style) Variable 'a' is assigned a value that is never used.\n"
+            "[test.cpp:4]: (style) Variable 'a' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("struct AB { int a; int b; } ab;\n"
                               "void foo()\n"
@@ -4491,7 +4575,9 @@ private:
                               "    int * a = &ab.a;\n"
                               "}");
         ASSERT_EQUALS("[test.cpp:5]: (style) Variable 'a' is assigned a value that is never used.\n"
-                      "[test.cpp:4]: (style) Variable 'ab' is not assigned a value.\n", errout.str());
+                      "[test.cpp:4]: (style) Variable 'ab' is not assigned a value.\n"
+                      "[test.cpp:5]: (style) Variable 'a' is assigned a value that is never used.\n", // duplicate
+                      errout.str());
 
         functionVariableUsage("struct AB { int a; int b; };\n"
                               "void foo()\n"
@@ -5105,7 +5191,10 @@ private:
                               "    struct ABC { int a, b, c; };\n"
                               "    struct ABC abc = { 1, 2, 3 };\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:4]: (style) Variable 'abc' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:4]: (style) Variable 'abc' is assigned a value that is never used.\n"
+            "[test.cpp:4]: (style) Variable 'abc' is assigned a value that is never used.\n", // duplicate
+            errout.str());
     }
 
     void localvarStruct3() {
@@ -5163,7 +5252,10 @@ private:
                               "    A a = { 0 };\n"
                               "    return 0;\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:3]: (style) Variable 'a' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (style) Variable 'a' is assigned a value that is never used.\n"
+            "[test.cpp:3]: (style) Variable 'a' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         // extracttests.disable
         functionVariableUsage("class A { int i; };\n"
@@ -5171,9 +5263,12 @@ private:
                               "    A a = { 0 };\n"
                               "    return 0;\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:3]: (style) Variable 'a' is assigned a value that is never used.\n", errout.str());
-        // extracttests.enable
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (style) Variable 'a' is assigned a value that is never used.\n"
+            "[test.cpp:3]: (style) Variable 'a' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
+        // extracttests.enable
         functionVariableUsage("class A { int i; public: A(); { } };\n"
                               "int foo() {\n"
                               "    A a;\n"
@@ -5459,7 +5554,10 @@ private:
                               "    else\n"
                               "        return 1;\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:3]: (style) Variable 'y' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:3]: (style) Variable 'y' is assigned a value that is never used.\n"
+            "[test.cpp:3]: (style) Variable 'y' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("int foo(int x)\n"
                               "{\n"
@@ -6117,12 +6215,18 @@ private:
         functionVariableUsage("void foo() {\n"
                               "    std::string s = \"foo\";\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:2]: (style) Variable 's' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:2]: (style) Variable 's' is assigned a value that is never used.\n"
+            "[test.cpp:2]: (style) Variable 's' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("void foo() {\n" // #8901
                               "    const std::string s = \"foo\";\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:2]: (style) Variable 's' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:2]: (style) Variable 's' is assigned a value that is never used.\n"
+            "[test.cpp:2]: (style) Variable 's' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("std::string foo() {\n"
                               "    std::string s;\n" // Class instances are initialized. Assignment is not necessary
@@ -6160,7 +6264,10 @@ private:
         functionVariableUsage("void foo() {\n"
                               "    const bool b = true;\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:2]: (style) Variable 'b' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:2]: (style) Variable 'b' is assigned a value that is never used.\n"
+            "[test.cpp:2]: (style) Variable 'b' is assigned a value that is never used.\n", // duplicate
+            errout.str());
     }
 
     void localvarconst2() {
@@ -6287,7 +6394,10 @@ private:
         functionVariableUsage("void f() {\n"
                               "    std::string x = foo();\n"
                               "}");
-        ASSERT_EQUALS("[test.cpp:2]: (style) Variable 'x' is assigned a value that is never used.\n", errout.str());
+        ASSERT_EQUALS(
+            "[test.cpp:2]: (style) Variable 'x' is assigned a value that is never used.\n"
+            "[test.cpp:2]: (style) Variable 'x' is assigned a value that is never used.\n", // duplicate
+            errout.str());
 
         functionVariableUsage("void f() {\n"
                               "    std::vector<int> x;\n"
@@ -6427,7 +6537,9 @@ private:
                               "    auto a2 = std::unique_ptr<A>(new A());\n"
                               "}\n");
         ASSERT_EQUALS("[test.cpp:7]: (style) Variable 'a' is assigned a value that is never used.\n"
-                      "[test.cpp:8]: (style) Variable 'a2' is assigned a value that is never used.\n", errout.str());
+                      "[test.cpp:8]: (style) Variable 'a2' is assigned a value that is never used.\n"
+                      "[test.cpp:8]: (style) Variable 'a2' is assigned a value that is never used.\n", // duplicate
+                      errout.str());
 
         functionVariableUsage("void g();\n" // #11094
                               "void f() {\n"
diff --git a/test/testvalueflow.cpp b/test/testvalueflow.cpp
index 6c8cea602..c7eda1981 100644
--- a/test/testvalueflow.cpp
+++ b/test/testvalueflow.cpp
@@ -1852,7 +1852,8 @@ private:
                 "}");
         ASSERT_EQUALS_WITHOUT_LINENUMBERS(
             "[test.cpp:3]: (debug) valueFlowConditionExpressions bailout: Skipping function due to incomplete variable a\n"
-            "[test.cpp:4]: (debug) valueflow.cpp:1260:(valueFlow) bailout: variable 'x', condition is defined in macro\n",
+            "[test.cpp:4]: (debug) valueflow.cpp:1260:(valueFlow) bailout: variable 'x', condition is defined in macro\n"
+            "[test.cpp:4]: (debug) valueflow.cpp:1260:(valueFlow) bailout: variable 'x', condition is defined in macro\n", // duplicate
             errout.str());
 
         bailout("#define FREE(obj) ((obj) ? (free((char *) (obj)), (obj) = 0) : 0)\n" // #8349
@@ -1862,7 +1863,8 @@ private:
                 "}");
         ASSERT_EQUALS_WITHOUT_LINENUMBERS(
             "[test.cpp:3]: (debug) valueFlowConditionExpressions bailout: Skipping function due to incomplete variable a\n"
-            "[test.cpp:4]: (debug) valueflow.cpp:1260:(valueFlow) bailout: variable 'x', condition is defined in macro\n",
+            "[test.cpp:4]: (debug) valueflow.cpp:1260:(valueFlow) bailout: variable 'x', condition is defined in macro\n"
+            "[test.cpp:4]: (debug) valueflow.cpp:1260:(valueFlow) bailout: variable 'x', condition is defined in macro\n", // duplicate
             errout.str());
     }
 
@@ -1876,7 +1878,8 @@ private:
                 "}");
         ASSERT_EQUALS_WITHOUT_LINENUMBERS(
             "[test.cpp:3]: (debug) valueFlowConditionExpressions bailout: Skipping function due to incomplete variable a\n"
-            "[test.cpp:2]: (debug) valueflow.cpp::(valueFlow) bailout: valueFlowAfterCondition: bailing in conditional block\n",
+            "[test.cpp:2]: (debug) valueflow.cpp::(valueFlow) bailout: valueFlowAfterCondition: bailing in conditional block\n"
+            "[test.cpp:2]: (debug) valueflow.cpp::(valueFlow) bailout: valueFlowAfterCondition: bailing in conditional block\n", // duplicate
             errout.str());
 
         // #5721 - FP