diff --git a/lib/checknullpointer.cpp b/lib/checknullpointer.cpp
index 1f9171a7ebb..7ef6b03d4ea 100644
--- a/lib/checknullpointer.cpp
+++ b/lib/checknullpointer.cpp
@@ -546,11 +546,11 @@ void CheckNullPointer::pointerArithmeticError(const Token* tok, const ValueFlow:
 
     std::string id = "nullPointerArithmetic";
     if (value && value->unknownFunctionReturn == ValueFlow::Value::UnknownFunctionReturn::outOfMemory) {
-        errmsg = "If memory allocation fail: " + ((char)std::tolower(errmsg[0]) + errmsg.substr(1));
+        errmsg = "If memory allocation fails: " + ((char)std::tolower(errmsg[0]) + errmsg.substr(1));
         id += "OutOfMemory";
     }
     else if (value && value->unknownFunctionReturn == ValueFlow::Value::UnknownFunctionReturn::outOfResources) {
-        errmsg = "If resource allocation fail: " + ((char)std::tolower(errmsg[0]) + errmsg.substr(1));
+        errmsg = "If resource allocation fails: " + ((char)std::tolower(errmsg[0]) + errmsg.substr(1));
         id += "OutOfResources";
     }
 
diff --git a/lib/library.cpp b/lib/library.cpp
index 9b6c46f4410..b6f801589d3 100644
--- a/lib/library.cpp
+++ b/lib/library.cpp
@@ -1597,6 +1597,10 @@ const std::string& Library::returnValue(const Token *ftok) const
 
 const std::string& Library::returnValueType(const Token *ftok) const
 {
+    while (Token::simpleMatch(ftok, "::"))
+        ftok = ftok->astOperand2() ? ftok->astOperand2() : ftok->astOperand1();
+    if (!ftok)
+        return mEmptyString;
     if (isNotLibraryFunction(ftok)) {
         if (Token::simpleMatch(ftok->astParent(), ".") && ftok->astParent()->astOperand1()) {
             const Token* contTok = ftok->astParent()->astOperand1();
diff --git a/test/cfg/opencv2.cpp b/test/cfg/opencv2.cpp
index 56eacfd5210..6e79caab8d0 100644
--- a/test/cfg/opencv2.cpp
+++ b/test/cfg/opencv2.cpp
@@ -45,7 +45,7 @@ void memleak()
 {
     // cppcheck-suppress cstyleCast
     const char * pBuf = (char *)cv::fastMalloc(1000);
-    // cppcheck-suppress [uninitdata, valueFlowBailoutIncompleteVar]
+    // cppcheck-suppress [uninitdata, valueFlowBailoutIncompleteVar, nullPointerOutOfMemory]
     std::cout << pBuf;
     // cppcheck-suppress memleak
 }
diff --git a/test/cfg/std.cpp b/test/cfg/std.cpp
index 48c4efc4418..a3345425d41 100644
--- a/test/cfg/std.cpp
+++ b/test/cfg/std.cpp
@@ -1854,6 +1854,7 @@ void uninitar_fopen(void)
     const char *mode;
     // cppcheck-suppress uninitvar
     FILE * fp = std::fopen(filename, mode);
+    // cppcheck-suppress nullPointerOutOfResources
     fclose(fp);
 }
 
diff --git a/test/testnullpointer.cpp b/test/testnullpointer.cpp
index 33352085208..31ac0abc492 100644
--- a/test/testnullpointer.cpp
+++ b/test/testnullpointer.cpp
@@ -4101,7 +4101,14 @@ class TestNullPointer : public TestFixture {
               "    *(p+2) = 0;\n"
               "    free(p);\n"
               "}");
-        ASSERT_EQUALS("[test.cpp:3]: (error) If memory allocation fail: pointer addition with NULL pointer.\n", errout_str());
+        ASSERT_EQUALS("[test.cpp:3]: (error) If memory allocation fails: pointer addition with NULL pointer.\n", errout_str());
+
+        check("void f() {\n" // #13676
+              "    int* q = static_cast<int*>(std::malloc(4));\n"
+              "    *q = 0;\n"
+              "    std::free(q);\n"
+              "}");
+        ASSERT_EQUALS("[test.cpp:3]: (warning) If memory allocation fails, then there is a possible null pointer dereference: q\n", errout_str());
     }
 
     void functioncall() {    // #3443 - function calls