diff --git a/lib/checkmemoryleak.cpp b/lib/checkmemoryleak.cpp
index addf8b18c..b1147b9c8 100644
--- a/lib/checkmemoryleak.cpp
+++ b/lib/checkmemoryleak.cpp
@@ -257,7 +257,7 @@ CheckMemoryLeak::AllocType CheckMemoryLeak::getDeallocationType(const Token *tok
         tok = tok->next();
 
     if (Token::Match(tok, "free|kfree ( %varid% ) [;:]", varid) ||
-        Token::Match(tok, "free|kfree ( %varid% -", varid) ||
+        Token::Match(tok, "free|kfree ( %varid% -|,", varid) ||
         Token::Match(tok, "realloc ( %varid% , 0 ) ;", varid))
         return Malloc;
 
diff --git a/test/testmemleak.cpp b/test/testmemleak.cpp
index a5a2e3794..ac30a35f0 100644
--- a/test/testmemleak.cpp
+++ b/test/testmemleak.cpp
@@ -163,6 +163,7 @@ private:
         TEST_CASE(simple7);
         TEST_CASE(simple9);     // Bug 2435468 - member function "free"
         TEST_CASE(simple11);
+        TEST_CASE(nonstd_free);
         TEST_CASE(new_nothrow);
 
         TEST_CASE(staticvar);
@@ -970,6 +971,13 @@ private:
         ASSERT_EQUALS("", errout.str());
     }
 
+    void nonstd_free() {
+        check("void f() {\n"
+              "    void* mem = malloc(100, foo);" // Non-standard malloc() implementation
+              "    free(mem, bar);" // Non-standard free() implementation (#5665)
+              "}");
+        ASSERT_EQUALS("", errout.str());
+    }
 
 
     void new_nothrow() {